The Formation of Large Garnets at Gore Mountain, New York:
Experimental partial melting of amphibolite and meta-gabbro
Jen Axler
Submitted to the Department of Geosciences
of Smith College
in partial fulfillment
of the requirements for the degree of
Bachelor of Arts
John B. Brady, Honors Project Advisor
May 15, 2011
Abstract
This study examined the hypothesis that partial melting aided the growth of large
garnets in the Barton Deposit of Gore Mountain, New York. Samples of meta-gabbro and
garnet amphibolite from Gore Mountain were ground into powders. The powders were
then subjected to temperatures and pressures resembling the peak conditions of the
Adirondack Highlands (800°C and 8 kb) using a piston cylinder press. Water was added
to half of the samples to determine if an influx of water had an influence on the melting
or garnet growth.
After each experiment, the nickel sample holder was mounted in epoxy and
ground to expose the contents of the run products. Melt was not identified within the
experimental samples. The results give no evidence that partial melting had an effect on
garnet growth, as melt did not appear to form readily under the peak temperature
conditions. Additionally, the results of this study show that the simple addition of water
did not convert the meta-gabbro into the garnet amphibolite ore. The process must be
more complex than purely hydrating the meta-gabbro to become amphibolite as garnets
of the hydrated meta-gabbros differed in composition from garnets of the Gore Mountain
garnet amphibolite.
i
Acknowledgements
First I would like to thank my advisor John Brady, who guided me through the whole
process of the formation and completion of this project. He taught me how to run the pistoncylinder press on my own. He also showed me how to analyze all of my samples on the Scanning
Electron Microscope. Most of all, he was always willing to talk about my project even on a spur
of the moment.
I would like to thank Mike Vollinger for making a device to help grind down my samples
and for being a morale booster. Additionally, I would like to thank Greg Young and Dale
Renfrow in the Center for Design and Fabrication for helping create items needed for
experiments.
I would like to thank my family for their support this year. I would also like to thank my
fellow Smith geology majors for making the department a warm, fun, and friendly place to work
in. The research was made more enjoyable in the company of those in the geology computer lab.
Finally, a thank you goes to all the professors at Smith who encouraged me and make Smith a
great place to grow.
ii
Table of Contents
Page Number
i
Acknowledgements
Abstract
ii
Index of Figures and Tables
iv-v
Introduction
Geologic Setting
Lithologies
1-3
1-2
2-3
Previous Works
6-8
Experimental Modeling
9-10
Experimental Methods
11-16
Results
Experiment 1
17-74
17-25
Experiment 2
26-33
Experiment 3
34-44
Experiment 5
45-53
Experiment 6
54-63
Experiment 7
64-74
Discussion
75-80
Conclusion
81
References
82
Appendix I: Additional Run Information
83-91
Appendix II: Chemical Analyses
92-110
iii
Index of Figures and Tables
Section
Figure #
Page #
Introduction
Experimental
Methods
1
2
3
4
Gore Mountain Garnet Ore
Location Map of Gore Mountain
Map of the Gore Mountain Amphibolite Ore Body
Open Pit Quarry at Gore Mountain
5
6
Sample Assembly
Piston Cylinder Apparatus
15
16
7
8
9
10
Original Sample Powders
Dry and Wet Coarse Meta-Gabbro 65X
Dry and Wet Coarse Meta-Gabbro 200X
Dry and Wet Coarse Met-Gabbro 650X
21
22
23
24
11
12
13
14
Dry and Wet Coarse Amphibolite 65X
Dry and Wet Coarse Amphibolite 650X
Dry and Wet Fine Amphibolite 65X
Dry and Wet Fine Amphibolite 650X
30
31
32
33
15
16
17
18
19
20
21
22
23
Dry and Wet Fine Ampibolite 65X
Dry and Wet Fine Ampibolite 650X
Chemical Profile of a Garnet from the Wet Ampibolite
Chemical Profile of a Hornblende from the Wet Ampibolite
Dry and Wet Fine Meta-Gabbro 65X
Dry and Wet Fine Meta-Gabbro 650X
Composition of Dry Meta-Gabbro Hornblendes
Composition of Dry Meta-Gabbro Orthopyroxenes
Composition of Wet Meta-Gabbro Hornblendes
38
39
40
40
41
42
43
43
44
24
25
26
27
Dry and Wet Fine Amphibolite 65X
Dry and Wet Fine Amphibolite 650X
Composition of Wet Amphibolite Hornblendes
Composition of Wet Amphibolite Garnets
49
50
51
51
4
4
5
5
Results:
Experiment 1
(800°C 8kb)
Experiment 2
(800°C 8kb)
Experiment 3
(900°C 8kb)
Experiment 5
(800°C 7kb)
iv
Experiment 6
(800°C 5kb)
28
29
Dry and Wet Fine Meta-Gabbro 65X
Dry and Wet Fine Meta-Gabbro 650X
52
53
30
31
32
33
34
35
Dry and Wet Fine Amphibolite 650X
Dry and Wet Fine Amphibolite 2000X
Chemical Profile of a Garnet from the Dry Amphibolite
Dry and Wet Fine Meta-Gabbro 650X
Dry and Wet Fine Meta-Gabbro 2000X
Chemical Profile of a Hornblende from the Wet Meta-Gabbro
58
59
60
61
62
63
36
37
38
39
40
41
42
Dry and Wet Fine Ampibolite 65X
Dry and Wet Fine Amphibolite 650X
Chemical Profile of a Hornblende from the Wet Ampibolite
Dry and Wet Fine Meta-Gabbro 65X
Dry and Wet Fine Meta-Gabbro 2000X
Composition of Dry Meta-Gabbro Hornblendes
Composition of Wet Meta-Gabbro Hornblendes
68
69
70
71
72
73
73
43
44
Ternary Plot of all Garnets Analyzed
Compositional Graph of all Hornblendes Analyzed
79
80
Experiment 7
(800°C 6kb)
Discussion
Tables
Table #
1
Bulk Rock Compositions
2
List of all Successful Experiments
17
3
Experiment 1: Wet Meta-Gabbro Hornblende Compositions
25
4
Experiment 1: Wet Meta-Gabbro Garnet Compositions
25
5
Experiment 5: Dry Amphibolite Hornblende Composition
45
6
Experiment 6: Wet Amphibolite Plagioclase Compositions
60
7
Experiment 6: Dry Meta-Gabbro Hornblende Compositions
63
8
Experiment 7: Wet Amphibolite Average Garnet Composition
70
9
Experiment 7: Wet Amphibolite Hornblende Compositions
70
10
Experiment 7: Wet Meta-Gabbro Garnet Compositions of varying sizes
74
2
v
Introduction
The Barton Deposit on Gore Mountain has been mined for its garnet continuously for 105
years. The ore consists of unusually large garnet porphyroblasts, many greater than 10 cm in
diameter (Fig. 1)
The origin of the garnets of Gore Mountain has been studied by many, yet there is not a
universally accepted explanation for the formation of the garnets. The genesis of the large garnet
crystals is generally attributed to an influx of water along the contact between the gabbro and the
syenite (Luther,1976, Goldblum and Hill, 1992). This is also said to have occurred under
granulite facies metamorphic conditions (Luther, 1976). If water is added to rocks at this high of
temperature and pressure, it would be likely for partial melting to occur. The presence of a partial
melt would increase the rate of diffusion thus aiding the growth of the garnet crystals.
In order to test the hypothesis that the garnets grew large because they were in the
presence of a partial melt, melting experiments were conducted on samples of the meta-gabbro
and the amphibolite from Gore Mountain using a piston-cylinder press. A variety of temperatures
and pressures were used to simulate the metamorphism these rocks underwent. In addition water
was added to some samples to determine the effects of volatiles.
Geologic Setting
Gore Mountain is located in the Adirondack Mountains of northern New York (Fig. 2).
Specifically, it is located in the Adirondack Highlands. The main rock types of the Adirondack
Highlands are anorthosite, syenite and gabbro, all of which have been metamorphosed during the
Grenville Orogeny up to granulite facies pressures and temperatures (McLelland, 1995). The
rocks are of the Grenville province and are Precambrian (~1.1 Ga) in age.
1
The garnet ore of Gore Mountain occurs within garnet amphibolite at an elevation around
2600 ft on the North slope of the mountain. The amphibolite body is thin, only 50 to 100m wide
and occurs in a dipping lens that follows an East-West trend and transitions to the north into
olivine meta-gabbro over 1-3m (Fig. 3). The garnet amphibolite is surrounded by meta-gabbro to
the north, meta-anorthosite to the east, and meta-syenite to the south. A fault occurs between the
meta-syenite and the garnet amphibolite and is one boundary for the ore body (Fig 3). The ore is
exposed in multiple open pit quarries (Fig. 4).
Lithologies
The olivine meta-gabbro has undergone granulite facies metamorphism. The mineralogy
of the meta-gabbro includes clinopyroxene, orthopyroxene, plagioclase, hornblende, garnet,
biotite, olivine, and opaque minerals likely to be ilmenite. Coronas of garnet formed between
plagioclase and clinopyroxene during the initial metamorphism of the meta-gabbro (Levin,
1960). Additionally, coronas of biotite and hornblende formed at the same time. The composition
of the meta-gabbro is almost the equivalent to the composition of the garnet amphibolite except
for the amount of water (Table 1). Thus, it is likely that the meta-gabbro was transformed into
the garnet amphibolite as water influxed into the margins of the gabbro body.
Table 1. The bulk rock compositions of Gore Mountain rocks completed by Heather Howard, Smith
College (unpublished data, 2004). The powders of these samples were used in the experiments.
The transition zone between the meta-gabbro and garnet amphibolite is only 1- 3m wide,
but has distinctive characteristics. The size of the garnet crystals increase towards the
2
amphibolite as they are less then 1mm in diameter in the meta-gabbro, 3mm in diameter within
the transition zone, and 50-350mm in the amphibolite (Goldblum and Hill, 1992).
The garnet amphibolite consists of hornblende, garnet, plagioclase, orthopyroxene, biotite
and sulfides. There is no olivine and very little if any clinopyroxene. In addition to an increase in
garnet size, amphibole and biotite also increase in size (Goldblum and Hill, 1992). The garnet is
not zoned and is homogenous throughout the ore body, averaging 13% in mode (Luther, 1976,
Glodblum 1988). It is believed that the garnet ore was created as the margin of the olivine metagabbro underwent retrograde metamorphism, particularly by an influx of water while the gabbro
remained hot (Luther, 1976; Goldblum and Hill, 1992).
The large size of the garnets is attributed to high rates of diffusion (Goldblum and Hill,
1992). Due to the fact that it takes large amounts of water to transform gabbro to amphibolite, it
is likely that the influx of water could have aided the growth of the minerals as it increases the
ability of elements to diffuse through the system.
3
5 in.
Figure 1. Gore Mountain Garnet Ore. Large garnets surrounded by hornblende occur
throughout the amphibolite.
Figure 2. Location Maps of Gore Mountain. (a)The dotted area marks the Grenville rocks of the
Adirondack Mountains. (b) The location of Gore Moutnain is marked by a red dot. Anorthosite
massifs of the Adirondack Mountains are shown in black. (Goldblum and Hill, 1992).
4
Figure 3. Map of the garnet amphibolite ore body and the lithologies that surround it. Located on
the bottom of the north slope of Gore Mountain. (Goldblum and Hill, 1992)
Figure 4. A photograph of one of the open pits previously mined for Gore Moutnain garnet.
5
Previous Work
The majority of work on the garnet ore of Gore Mountain has focused on the mineralogy,
petrology, and chemistry of the local rock units. Below are summaries of various research that
has been completed over the years.
Levin (1950) describes the garnet ore forming as a result of contact metamorphism as the
syenite magma intruded adjacent to the meta-gabbro. He classified the garnet of the Gore
Mountain area into four different types; C-type or microscopic corona crystals, P-type or
poikiloblastic crystals, X-type or completely recrystallized prophyroblasts, and XH-type which
are garnet porphyroblasts greater than an inch that are surrounded by a hornblende shell. Levin
(1950) proposes that the garnets of the meta-gabbro and meta-anorthosite formed as a result of
the intrusion of the syenite magma. Specifically, he postulates that the largest garnets formed
where the syenite magma mixed with the country rock and that the garnets also formed due to
contact metamorphism. As the temperature decreased with distance so did the size of the garnets
the further away from the contact. This hypothesis is disputed as Buddington (1952) found the
garnets within the syenite to have a different composition than the garnets within the metagabbro.
The origin of the hornblende rims and chemical analysis of minerals and rocks from Gore
Mountain:
Bartholome (1960) concluded that the garnet porphyroblasts are not present in rocks that
have retained relics of their magmatic texture and mineralogy. Thus, the large garnets must have
formed in place due to metamorphic processes and are not xenoliths. Bartholome (1960) also
determined that the rims surrounding the garnets and the garnets grew concurrently. The
hornblende that forms rims around the garnet is richer in magnesium and silica and poorer in
6
alumina than the hornblende of the matrix (Bartholome, 1960). Additionally Bartholome’s
(1960) chemical analysis shows that the garnet rim hornblende has more than four times the
amount of fluoride than the matrix hornblende however, two different people did the analyses.
A petrologic look at the origin of Gore Mountain garnet:
Luther (1976) determined the chemical reaction that transformed the gabbro into the
garnet amphibolite. He suggested the following:
19 pl + 8cpx+ 10opx+4ol+6H2O+1mt 6h +3pl+4g+1opx
(pl=plagioclase, cpx=clinopyroxene, opx=orthopyroxene, ol=olivine, mt=magnetite, h=hornblende, g=garnet)
However, this reaction was determined for conditions at 1 kb and 20°C and does not take into
account the changes that occur to minerals and water under 7-8kb and 800°C. Luther (1976) used
an electron microprobe analysis to obtain the composition of the garnets. He found that the
garnets were weakly zoned, indicating that the environment in which the garnets grew had little
variation. Luther (1976) described the rims around the garnet as matrix depletion rims if the
reaction above is true.
Gore Mountain Ore: The result of a shear zone
Goldblum and Hill (1992) propose that the large garnets formed as a result of the
combination of high temperatures and an influx of water within a shear zone between different
lithologies. The meta-gabbro deforms in a brittle manner even under granulite facies
metamorphism. If the gabbro was strained along a weaker lithology, (such as syenite) fractures
would be produced within the meta-gabbro along the contact and thus would provide means for
7
water to flow through. The presence of water would increase the rate of diffusion aiding the
growth of minerals and allowing hornblende to replace pyroxene. The large size of crystals in the
amphibolite is likely a result of a high rate of diffusion allowing the minerals to receive the
necessary ions to grow larger. Additionally, the strain will cause defects in minerals creating
sites that favor additional mineral growth. Observations by Luther (1976) support this as he
reported the largest garnets in both the garnet amphibolite and the anorthosite have parallel sets
of partings spaced a few millimeters apart. If this is true, that the shear zone must have been
actively shearing as the garnets grew.
Dehydration melting of an amphibolite:
The peak metamorphic condition of the Adirondack Highlands is thought to be 800°C
and 8 kbars (McLelland, 1995). At 10kbars powdered amphibolite begins to melt below 850°
(Wolf and Wyllie, 1994). Thus, at 8kbars the amphibolite at Gore Mountains is likely to have
begun melting. Although the whole rock body would not be melted at this temperature, magma
would begin to develop. With the addition of volatiles, particularly water, the melting point
would be lowered thus causing more magma to be generated. Wolf and Wyllie partially melted
amphibolite and were able to grow garnet (1993). While garnet grew largest between 925 and
950°C at 10kbars during their experiments, the reaction also occurred at lower temperatures
when the amphibolite was under those conditions for longer periods of time. Although the
composition of the amphibolite used by Wolf and Wyllie has 6.0% more CaO, 4.15% less FeO,
and 3.18% less Al2O3 than the amphibolite of Gore Mountain, the same partial dehydration
melting could be applied to the rocks of Gore Mountain.
8
Experimental Modeling
Using the program MELTS predictions of the experimental results can be predicted
for various pressures and temperatures (Asimow and Ghiroso, 1998; Ghiroso and Sack, 1995).
The chemical analyses of the gabbro and garnet- amphibolite from the eastern and western
sequences were used (Luther, 1977). Pressures of 7kb and 8kb were used with temperatures
ranging from 700°C to 1000°C. Water was also added to a number of the models. The garnet
calculated by MELTS generally has less calcium in it than the garnet at Gore Mountain for any
given model. Not all combinations of temperatures, pressures, and water content produced
results from MELTS.
Eastern Gabbro
Modeling without water
MELTS predicts the liquidus of the gabbro to occur at 1388°C at 8kb. At
8kb and 1000°C, the gabbro is expected to be 12.3% liquid, with no garnet formed. At 950°C the
gabbro the model predicts that there will be 12.96% garnet along with 9.48% liquid. At 8 kb,
MELTS predicts that garnet will begin to form in the eastern gabbro around 975°C and garnet
will increase with lower temperatures.
At 7kb the liquidus is expected to be at 1360°C. MELTS predicts that at 900°C and 7kb
there will be 13.86% garnet and 3.88% liquid. Additionally, at 900°C and 7kb the gabbro is still
expected to contain olivine, hornblende, and biotite, which was not predicted for the models at
8kb.
Modeling with 5% water added
At 7kb, with the addition of 5% water, MELTS predicts the liquidus to occur at
9
1305°C. At 900°C 8.13% garnet is expected along with 39.74% liquid. If the temperature is
lowered to 700°C the percentage of garnet increases to 36.35% and the percentage of liquid
decreases to 17.13%. At 700°C, MELTS predicts the presence of clinoamphibole, leucite, and
biotite, all three of which were not predicted for 900°C.
Eastern Amphibolite
Modeling without water
At 8kb the liquidus of the amphibolite is expected to be at 1322°C. If the
temperature of the model is set to 950°C, MELTS predicts that 22.85% of the amphibolite would
be garnet, 18.94% would be liquid, and 46.27% clinopyroxene. No hornblende is predicted
which is likely the result of the complexity of the thermodynamics of the formation of
hornblende. It is likely that much of the clinopyroxene predicted would actually be hornblende.
If the temperature is lower to 850°C, the altered amphibolite is predicted to have 36.68% garnet,
33.13% clinopyroxene, 3.68% biotite, 4.03% hornblende, and 7.08% liquid. The MELTS results
support the possibility of partial melting under the conditions of metamorphism that was
suggested by others. This data helped guide the choice of temperature for the experiments.
10
Experimental Methods
In general, the run procedure was similar to that of Morse et al. (2004), but using the
nickel sample holder of Ayers et al. (1992). Rock samples from Gore Mountain were crushed
and ground into powder. Some of each was ground to finer sizes using a micro-mill reducing the
largest grain size by half. The coarse amphibolite powder grain size ranged from <1µm to
100µm, while the fine amphibolite powder ranged in size from <1µm to 50 µm. The coarse
meta-gabbro ranged in sized from <1µm to 30µm, while the fine meta-gabbro ranged in size
from <1µm to 15µm. Two meta-gabbro samples from Gore Mountain were used in experiments,
GM-307, GM-308, both of which have similar compositions. Only one amphibolite sample was
used (GM-407). Each powder was dehydrated for at least an hour in a 110°C oven before
insertion into the sample holders.
Sample Assembly:
The sample assembly consists of many parts as shown in Figure 6. The thermocouple is
placed close to the sample powders to ensure an accurate temperature reading. The dimensions
of the sample assembly’s parts also ensure that the temperature is highest at the center of the
nickel sample holder. Because of its good thermal conductivity, the use of a Ni holder reduces
temperature gradients during the experiments. Salt sleeves, and magnesium oxide spacers were
made custom for each individual experiment. A W-Rb thermocouple was used to monitor and
conrol the temperature of the experiment and is newly made for each run.
Four open gold capsules, welded closed at one end, are placed into holes within a nickel
sample holder with an oxidized surface. As each powder was added to the sample holder, the
amount of powder was weighed. The amount of powder used for each experiment sample was
11
between 0.0100 -0.0300g depending on the amount of space available in the gold capsule. If any
water was added to the capsule, it was done before the powder was added to the gold capsule,
and the amount of water was carefully weighed. Tape was used to cover empty sample capsules
as well as previously filled capsules to minimize the possibility of contamination between
capsules. Once all of the gold capsules are filled, the nickel sample holder can be placed within a
fired prophyllite cup. A small sheet of gold is used to cover the sample capsules and seals the
capsules once pressure is applied to the sample assembly. A nickel cap to the nickel sample
holder is then place on top followed by the lid to the fired prophyllite cup. In a few cases, extra
space was observed between the nickel sample holder and the fired prophyllite cup. When space
was observed, it was filled with graphite powder before the lid is placed.
The next steps in the production of the sample assembly involved placing a graphite
furnace within a hollow pyrex sleeve, which was then surrounded by 2 halite sleeves. The
lengths of each individual sleeve varied, but the total length of both sleeves together was always
equivalent to the length of the pyrex sleeve. A cap to the bottom of the furnace was glued into
place, and fits within the pyrex sleeve. The bottom magnesium oxide spacer is then inserted into
the furnace, making sure it went down to the bottom of the furnace. The fired prophyllite cup
assembly was then placed within the graphite furnace. Next, the top magnesium oxide spacer is
placed within the furnace. The sample assembly is almost complete at this point. The last step
was to place a fitted rectangle of lead foil around the circumference of the assembly. A small
length (1-3mm) of lead foil is folded over the bottom of the sample assembly to hold it in place.
The lead foil acts as a lubricant between the sample assembly and the press. Now the sample
assembly can be placed within the pressure vessel of the piston-cylindar press. A stainless steel
12
base plug surrounded by an unfired prophyllite base plug sleeve was then gently placed on top of
the sample assembly within the pressure vessel.
Thermocouple Assembly:
Two Type D wires, one W97Re3 and the other W75Re25, were thread into two, four hole
thermocouples sleeves. Together the length of the sleeves totaled around 2.5 inches. At the ends
of the thermocouple sleeves the wires were then crossed and reinserted into a new hole within
the thermocouple sleeve.
Piston Cylinder Apparatus:
All runs were completed using the piston-cylinder press shown in Figure 7. The peak
metamorphic conditions for Gore Mountain were around 800°C and between 7 and 8 kbars
(McLelland, 1995). Because of this and because of the MELTS calculations the sample powders
were subjected to temperatures of 800 to 900°C at 5 to 8 kbars for 1-6 days. The lower pressures
were used to increase the amount of melt within the samples. To end a run, the power to the
graphite furnace is shut off. Because the furnace no longer generates heat to the sample, the
flowing water cools the sample quickly (a few seconds to cool several hundred °C). This will
immediately quench the sample and all melt should become glass.
Post-Run Sample Preparation
After each run, the nickel cylinder was removed from the sample assembly. It was then
glued into a 1-inch phenolytic cylinder holder using epoxy. The sample was ground using a lap
wheel until the four samples within the gold capsules were visible. This required the nickel lid
and the gold sheet to be ground through. For a better polish, the sample was then polished with
13
diamond grit down to 1 micron using a different lap wheel. This polished the sample enough to
be ready for the Scanning Electron Microscope (SEM). Before the sample could be analyzed
using the SEM, it had to be carbon coated using a carbon evaporator.
14
0.500
WRe Thermocouple
4-hole Alumina Tubing
Stainless Steel
Pyrophyllite
Sample
Sample
Pressed Halite
1.750
Fired Pyrophyllite
MgO
Pyrex Glass
Graphite
Gold Tubing
Nickel
Scale: 1" = 0.250
0.738
0.553
Figure 5. Diagram of Sample Assembly. The various parts and their materials of the sample
assembly is illustrated . The rock powder is placed in the area marked sample in the center of
the assembly. The thermocouple read the temperature near the top of the samples.
15
Main Power
Upper and Lower
Ram Pressures
Current
Temp. and
Output Power
Air and
Water
Sources
Figure 6. Piston-Cylider Apparatus. The apparatus puts the samples under high pressures and
temperatures to mimic conditions deep within the Earth’s crust. The important parts of the press are
labeled.
16
Results
The general format of the results separates the experiments into the individual powder
samples with and without water. The minerals of the samples were labeled in red on many of the
images. Crystals circled in red have been chemically analyzed using the SEM and have been
given unique names to identify them. Chemical line scans of crystals are shown as red lines
across the area of the crystal that was analyzed. The original rock powders used can be seen in
Figure 7. They can be compared with the results of experiments to see if any change in crystal
size occurred.
Experiment
Number
Temperature
Pressure
Duration
1
800°C
8 kbars
1 day 21 hours
2
800°C
8 kbars
1 day 21.5 hours
3
900°C
8 kbars
6 days 3.5 hours
5
800°C
7 kbars
6 hours
6
800°C
5 kbars
2 days 21 hours
7
800°C
6 kbars
4 days
Table 2. A table of all of the successful experiments with the temperature and
pressure conditions as well as the duration.
Experiment 1: 800°C, 8kb, 1 day 21 hours
Two different samples of meta-gabbro (GM-307 and GM-308) were used in this run. The
experiment consisted of a dry sample of each and a wet sample of each, containing 6-7% water.
The experiment ran for about 21 hours. Due to the similarities between the two samples of metagabbro, the results of only one of the powders is discussed below. See Figure 8 for images of
both samples of GM-307.
17
Dry Meta-Gabbro
The dry meta-gabbro has a wide range of crystal sizes. The majority of crystals are very
angular (Fig. 8a). The primary minerals are plagioclase and orthopyroxene. Hornblende and
garnet are also present, but less abundant. Clinopyroxene, olivine, and sulfides occur in minor
amounts. Some of the plagioclase crystals have an abundance of inclusions. Fractures can be
seen in the largest crystals (Fig. 8a). Many holes can be seen as highly charged areas (very
bright) within the secondary electron images of the sample (Figs. 8a and 9a). The holes are
irregularly shaped and occur primarily around grain boundaries. Other highly charged areas
include fractures within grains. In BEI photos, garnet is the brightest mineral, hornblende is gray
and plagioclase is dark gray to black. Orthopyroxene and clinopyroxene are bright, but not as
bright as garnet (brighter than hornblende).
A greater magnified image of the same sample of dry meta-gabbro can be seen in Figure
10a. One plagioclase crystal in view stands out as it has many inclusions. A chemical analysis of
the inclusions was attempted, however the total compound percent was too low making it likely
to be inaccurate. The two garnets circled (Grt-1.dg.1 and Grt-1.dg.2) were chemically analyzed
(Fig. 10a). The garnets are very similar in composition. The greatest difference in chemistry
occurs in the amount of iron, however this is only a 0.55% compound difference, which is
equivalent to a difference of 0.046 numbers of ions per formula of FeO. Thus despite the textural
difference of appearance of the two garnets, they are almost identical in composition. Remnant
olivine is found only in this experiment’s samples of dry meta-gabbro. No crystal zoning was
strikingly apparent looking at the compositional image of the sample.
The chemistry of other minerals was determined; however they are not located within the
image above. Clinopyroxene occurs within the dry meta-gabbro. The chemical formula of one of
18
the clinopyroxenes present, Cpx-1.dg.1, is Na0.09Ca0.85Mg0.76Fe0.22Al0.11(Al0.08Si1.92O6). The
composition if an olivine crystal was also found, the crystal, Ol-1.dg.1, has the chemical
formula: Na0.042Mg1.19Fe0.76(Si1.01O4). The olivine has almost double the weight percent of
magnesium versus iron, however it is closer toward the middle of the Fayalite-Forsterite
spectrum. The chemistry of a plagioclase crystal, Pl-1.dg.1, was determined to be:
Na0.59Ca0.40K0.02(Al1.44Si2.56O8). Additionally the composition of an orthopyroxene, Opx-1.dg.1,
was found to be: Na0.03Mg1.64Fe0.25 (Si2.05O6).
Wet Meta-Gabbro
The sample of wet meta-gabbro contains a larger amount of hornblende than the dry
meta-gabbro sample. In fact, hornblende is the predominate mineral of the modified wet metagabbro. Orthopyroxene and plagioclase are still present, but much less abundant as evident when
comparing Figure 8a to 8b with plagioclase shown as the darkest mineral. Inclusions also occur
within plagioclase crystals of the wet meta-gabbro. The abundance of garnet does not appear to
have changed between the dry meta-gabbro and the wet meta-gabbro. The crystals are angular to
sub-angular. The nature of the highly charged areas of the secondary electron image has changed
(Compare Fig. 8a to 8b and Fig. 9a to 9b). The holes appear to be vesicles of some sort as they
are rounded and not as irregularly shaped as they were within the dry sample. The overall
appearance of the wet meta-gabbro is much cleaner, or rather less chaotic looking. The wet
sample has an overall smooth texture while the dry sample does not.
Some zoning is evident within a hornblende crystal (Fig. 10b). Two separate chemical
analyses were completed on different parts of the crystal (Table 2). An analysis of the center of
the crystal was taken (Hbl-1.wg.1) along with one of the edge of the crystal (Hbl-1.wg.1a) (See
Fig. 10b). There is a major difference in composition of the two hornblendes. The center of the
19
crystal is richer in calcium, titanium, and potassium, while the edge of the crystals is greater in
iron. The other elements that constitute hornblende are only varying in small amounts between
the different parts of the crystal.
A crystal of garnet, Grt-1.wg.1, occurs between the two different parts of the hornblende
crystal (Fig. 10b). It is small compared to the hornblende crystal and its edges are rounded,
although it is not circular in shape. The garnet appears to have formed before the outer,
chemically different edge of the hornblende did as most of its edge touches the center part of the
hornblende. The edge of the hornblende crystal even separates from the center part of the crystal
near its contact with the garnet.
A second garnet, Grt-1.wg.2, was analyzed within Figure 10b. This garnet is slightly
different from the first garnet, Grt-1.wg.1. Grt-1.wg.2 is rectangular in shape with angular
edges. It has slightly more magnesium, aluminum, and calcium, but with less silica, iron,
manganese and potassium than Grt-1.wg.1 (Table 3). The difference for each individual
compound is less than 3.5%.
20
Coarse Amphibolite GM -407
Coarse Meta-Gabbro GM-307
Milled/Fine Amphibolite GM -407
Milled/Fine Meta-Gabbro GM-307
Figure 7 . The sample powders used in experiments. The variation in crystal sizes can be seen between each
powder. Both amphibolite powders have larger crystals than either meta-gabbro powder.
21
a.
200 μm
200 μm
b.
200 μm
200 μm
Figure 8. Meta-gabbro samples from Experiment 1 (800°C and 8kbars) shown at 60X magnification
(GM-307). (a)The dry meta-gabbro sample in BEI on the left and the dry meta-gabbro sample shown in
SEI on the right. (b) The wet meta-gabbro sample shown in BEI on the left the wet meta-gabbro sample
shown in SEI on the right.
22
a.
100 μm
100 μm
b.
100 μm
100
Figure 9 . Meta-gabbro samples from Experiment 1 (800°C and 8kbars) shown at 200X magnification
(GM-307). (a)The dry meta-gabbro sample in BEI on the left and in SEI on the right. (b) The wet metagabbro sample shown in BEI and in SEI on the right.
23
Hbl
Opx
Pl
Hbl
Hbl
Pl
Grt
Cpx
Hbl
Hbl
Hbl
Grt-1.dg.1
Opx
Ol
Pl
Ol
Pl
Pl
Hbl
Opx
Grt
Grt-1.dg.2
Pl
Hbl
Ol
Pl
a.
20 μm
Pl
Hbl
Hbl-1.wg.1a
Hbl-1.wg.1
Hbl
Hbl
H
Grt-1.wg.2
Grt-1.wg.1
bl
Hbl
Hbl
b.
Hbl
20 μm
Figure 10. Meta-gabbro samples from experiment 1 shown at 650X magnification with mineral
identifications (GM-307). The circled crystals have been chemically analyzed around the center of
the circle. (a)The dry meta-gabbro sample in BEI. (b)The wet meta-gabbro sample shown in BEI.
24
Exp 1
Na2O
MgO
Al2O3
SiO2
K2O
CaO
TiO2
MnO
FeO
Total
Hbl-1.wg.1
Hbl-1.wg.1a
Difference
Difference
Compound % Nos. of ions Compound % Nos. of ions Compound % Nos. of ions
2.59
0.77
3.23
0.91
0.64
0.15
12.79
2.92
13.38
2.91
0.59
0.00
13.89
2.51
17.26
2.97
3.37
0.46
39.45
6.04
41.79
6.10
2.34
0.06
1.57
0.31
0.14
0.03
1.44
0.28
11.46
1.88
8.23
1.29
3.23
0.59
2.16
0.25
0.58
0.06
1.58
0.19
0.04
0.01
0.19
0.02
0.15
0.02
10.34
1.32
12.41
1.52
2.07
0.19
23.00
23.00
94.30
16.00
97.20
15.82
Table 3. Table of the composition of a hornblende from the wet meta-gabbro of Experiment 1.
Hbl-1.wg.1 is the center of the crystal. Hbl-1.wg.1a is the edge of the crystal.
Grt-1.wg.1
Grt-1.wg.2
Difference
Difference
Compound % Nos. of ions Compound % Nos. of ions Compound % Nos. of ions
Na2O
0.55
0.08
0.42
0.06
0.13
0.02
MgO
8.14
0.91
9.85
1.13
1.71
0.22
Al2O3
22.15
1.96
22.45
2.03
0.31
0.08
SiO2
42.20
3.16
38.89
2.99
3.31
0.18
K2O
0.20
0.02
0.07
0.01
0.13
0.01
CaO
4.75
0.38
5.59
0.46
0.84
0.08
TiO2
0.04
0.00
0.04
0.00
0.00
0.00
MnO
0.62
0.04
0.52
0.03
0.11
0.01
FeO
21.53
1.35
20.47
1.31
1.07
0.04
12.00
12.00
Total
100.18
7.90
98.30
8.03
Table 4. Table of the composition of garnets from the wet meta-gabbro of Experiment 1.
25
Experiment 2: 800°C, 8kb, 1days 21.5 hours
Two different samples of amphibolite (GM-407) one coarse, and one milled to a finer
grain size were used. The coarse amphibolite powder grains range from less than 1µm to 100µm.
The finer amphibolite powder grains range from less than 1µm to 50µm. For each type (coarse
and fine), a dry sample and a wet sample were used. Between 5 and 6 weight percent water was
added to the wet samples. The samples were held at 800°C and 8kb for around 45.5 hours. See
Figures 11 and 13 for images of all samples.
Coarse Dry Amphibolite
This sample is predominately hornblende. Plagioclase is the second most common
mineral. Garnet and orthopyroxene are also major constituents of the amphibolite. The crystals
are angular to sub angular. The largest crystals are less than 200µm wide, but greater than
150µm wide (Fig. 11a). There are large crystals of every major mineral that occurs within the
amphibolite. Many of the highly charged areas within the secondary electron image are vesicles
that are believed to be due to a fluid created as the amphibolite reacted to the rise in temperature
and pressure. The fluid is a super critical H2O fluid that vaporizes upon quenching the
experiment and is a believed to be from the dehydration of hornblende, although it may have
exsolved from a melt on quench. The vesicles are around 10µm wide.
A closer look at the coarse amphibolite further reveals the angular nature of the crystals
(Fig.12a). No zonation is apparent in either the amphibole or the garnet. There could be minor
chemical variation within plagioclase crystals along the edges of holes, however they are likely
26
variations in thickness. The coarse dry amphibolite does not appear to have reacted much to the
rise in temperature and pressure.
Coarse Wet Amphibolite
The mineral assemblage of the coarse wet sample is very similar to the dry sample. Its
major minerals are hornblende, plagioclase, garnet and orthopyroxene with minor clinopyroxene.
Comparing Figure 11a to Figure 11b, there may be a larger percentage of plagioclase within the
wet sample. The crystals are sub-angular to sub-rounded and have a similar range in size. There
does appear to be more vesicles within the wet sample. The majority of crystals within the wet
sample are not zoned; however there are a few hornblende crystals that appear to be zoned.
A more highly magnified view of the coarse wet amphibolite can be seen in Figure 12b.
The plagioclase crystals appear to be less angular than other minerals. The large garnet crystals
appear to have been fractured and broken in to pieces during the experiment. The composition of
one garnet crystal, Grt-2.wa.1, was determined to be: Ca0.30Fe1.35 Mg1.24 Mn0.04 Al2.01(Si3.00O12).
The calcium content is only 3.7 weight percent, and the amount of magnesium is 11.0 weight
percent, while the iron content is 21.4 weight percent.
Fine Dry Amphibolite
The finely powdered amphibolite is composed majorly of hornblende and plagioclase.
Garnet and orthopyroxene are also present in significant amounts. Small vesicles occur within
the sample (Fig. 13a). The crystals are generally angular and have a smaller range in size than
previous samples. Further milling the amphibolite clearly created a finer powder. There does not
appear to be any organization of crystals occurring or any major pockets of smaller sized crystals
within the sample (Fig. 13a).
27
Looking at the fine, dry amphibolite in a closer view in Figure 14a, the nature of the
sample can be seen more easily. The vesicles occur primarily on crystal boundaries especially
around plagioclase crystals. There does not appear to be any zonation of crystals. Two garnet
crystals within the sample were analyzed (Grt-2.da.1 and Grt-2.da.2). They were almost identical
in composition. The average composition for the garnets is:
Ca0.30Fe1.38Mg1.23Mn0.04Al2.03(Si2.99O12). This is the same composition as a garnet from the wet
coarse amphibolite sample (Grt-2.wa.1).
Wet Fine Amphibolite
This sample is also composed primarily of plagioclase and hornblende with less, but
significant amounts of garnet and orthopyroxene. Figure 13b shows the complete sample of the
wet, fine amphibolite. There are two distinct ranges in crystal sizes. Pockets of smaller sized
(~1µm) crystals occur within the sample. This phenomenon does not occur within the equivalent
dry sample. The pockets appear to have the same mineralogy and proportions as the larger
crystal areas. A large amount of rounded vesicles can be seen in the secondary electron image of
Figure 13b. The vesicles are much larger than they were in the dry fine amphibolite sample.
There are vesicles within the pockets of fine crystals however; they are smaller and less abundant
than in the majority of the sample.
Figure 14b shows a place within the sample where the coarser area adjacent to the finer
area. Chemical analysis if the finer area was difficult because of the small size of the crystals.
Once again, looking at Figure 14b, it is clear that the vesicles are larger within the coarse area of
the sample. Two garnets were analyzed within the coarse area and one was analyzed within the
fine area. The garnet within the fine area was compared to the average composition of the
28
garnets within the coarse area because the coarse garnets were similar (Fig. 14 b). The garnet
within the fine area has 6.6% more magnesium, 8.7% more silica, and 1.4% more calcium than
the coarse garnets. The same fine garnet has 11.7% less alumina and 8.2% less iron. The fine
garnet has a clearly different composition than the coarse garnets.
29
a.
200 μm
2
b.
2
2
μ
μ
Figure 11. The two coarse amphibolite samples from experiment two held under 800°C and 8kbars at 65X
magnification. For each, the images on the left are BEI’s and the images on the right are SEI’s. (a) The
dry sample of the coarse amphibolite. (b) The wet sample of the coarse amphibolite with 5.74 weight
percent water added.
30
Hbl
Grt
Opx
Hbl
Hbl
Opx
Grt
Hbl
Hbl
Pl
Hbl
Opx
Pl
Pl
Opx
Grt
Grt
Hbl
Hbl
Hbl
Opx
Hbl
Grt
Grt
Pl
Hbl
Pl
Hbl
Hbl
a.
Pl
Pl
Hbl
Hbl
Pl
Cpx
opx
Hbl
Grt
Hbl
Pl
Grt
Grt-2.wa.1
Pl
Hbl
Pl
Pl
Pl
Grt
Pl
b.
Figure 12. Mineral identifications for the coarse amphibolite samples put at 800°C
and 8kbars at 650X magnification as BEI’s. (a) The dry coarse amphibolite sample.
(b) The wet coarse amphibolite sample.
31
a.
2
b.
2
2
μ
2
Figure 13. The two fine amphibolite samples from experiment two held under 800°C and 8kbars 65X
magnification. For each, the images on the left are BEI’s and the images on the right are SEI’s. (a) The dry
sample of the fine amphibolite. (b) The wet sample of the fine amphibolite with 5.07 weight percent water
added.
32
Hbl
Pl
Grt
Pl
Pl
Grt-2.da.2
Opx
Hbl
Pl
Grt
Pl
Pl
opx
Hbl
Hbl
Opx
Opx
Grt
Hbl
Pl
Pl
Hbl
Grt-2.da.1
Pl
Opx
opx
Hbl
Hbl
Hbl
Pl
Pl
Pl
Grt
Hbl
Pl
Hbl
Pl
a.
Pl
Pl
Pl
Grt-2.wa.2
Opx
Pl
Hbl
Grt-2.wa.3
Hbl
Hbl
Hbl
Pl
Hbl
Hbl
Hbl
Hbl
Grt
Grt
2 wa 4
Opx
b.
Figure 14. Mineral identifications for the fine amphibolite samples put at 800°C and
8kbars at 650X magnification as BEI’s. (a) The dry fine amphibolite sample.
(b) The wet fine amphibolite sample.
33
Experiment 3: 900°C, 8kb, 6 days 3.5 hours
The third experiment was a run with the amphibolite and the meta-gabbro. A wet and dry
sample of each was placed within the sample holder and put under 8 kbars of pressure and 900°C
of temperature. The samples were held at those conditions for 6 days and a few hours. All of the
sample powders were milled to a finer size for this experiment (Fig.7). The powders were milled
to create more surface area within the powder promoting crystal interaction during the
experiment.
Dry Amphibolite
The dry amphibolite contains angular to sub-angular crystals around 18µm wide (Fig.
15a). Hornblende is the most abundant mineral, followed by plagioclase. Garnet comprises about
10% of the sample. Orthopyroxene is also present, but is less abundant than the four minerals
mentioned above. Very small vesicles can be seen within the SEI image of the sample (Fig 15a).
Looking closer at the dry amphibolite, the texture of the sample is clear (Fig. 16a). The
edges of crystals are jagged. Holes occur primarily within the plagioclase crystals. The
orthopyroxene present tends to occur in smaller crystals around 10µm wide. There is no obvious
chemical zoning in the BEI image of the sample.
The two garnets analyzed (Grt-3.da.1 and Grt-3.da.2) in Figure 14a have almost identical
compositions. Their average chemical formula is: Ca0.41Fe1.34Mg1.18Mn0.04Al2.02(Si2.98O12). The
two hornblendes chemically analyzed (Hbl-3.da.1 and Hbl-3.da.2) also have similar
compositions. Their average chemical composition is
K0.16Na0.64(Na0.24Ca1.76)(Fe1.31Mg2.71Ti0.16Al0.85)(Al1.82Si6.18)O22(OH)2. The orthopyroxene
analyzed has the composition: Na0.03Ca0.02Fe0.60Mg1.31Al0.05(Al0.04Si1.96O6).
34
Wet Amphibolite
The wet-amphibolite sample has been altered greatly during the run. The crystals have
grown considerably compared to the size of the starting material. The vesicles within the wet
sample are larger than those of the dry sample (Fig. 15b). The edges of crystals are smooth and
rounded. Plagioclase appears to be interstitial and surrounded many of the smaller crystals (Fig.
16b). Many crystals show zonation, in particular, hornblende has the most visible zonation.
Chemical analysis was completed on a number of crystals. The average composition of
garnet was found to be: Ca0.30Fe1.45Mg1.22Mn0.04Al1.99(Si2.99O12). This is a different composition
than the garnets of the dry amphibolite. Two chemical cross-sections of garnets were made to see
if the garnets were zoned or homogenous throughout (Grt-L3.wa and Grt-L3.wa.2 in Fig 16b).
Figure 17 shows the counts for the major elements of garnet of line Grt-L3.wg. There is no
zoning within the garnet, it is completely homogenous. The same result was found for the other
garnet cross-section. A plagioclase crystal was also analyzed (Pl-3.wa.1) and found to have the
following composition: Na0.45Ca0.55Al1.59Si2.41O8.
A chemical cross-section of a hornblende crystal revealed different results. Figure 18
shows the profiles of elements in which zoning is apparent. In particular, potassium has the
greatest change throughout the crystal. The hornblende has a greater amount of potassium within
its center than on the edges or the newly grown material. There is slightly less magnesium and
aluminum, but more calcium within the center of the hornblende. A smaller hornblende
surrounded by plagioclase (Hbl-3.wa.2) has the following composition:
K0.15Na0.43(Na0.33Ca1.67)(Fe1.40Mg2.77Ti0.16Al1.08)(Al1.68Si6.32)O22(OH)2.
35
Dry Meta-Gabbro
The dry meta-gabbro has two distinct crystal sizes. The larger crystals are around 10µm
in diameter and comprise more than half of the sample. The smaller crystals average around 1µm
and occur in pockets within the sample (Fig. 19a). Vesicles within the sample are larger and
more abundant in the areas with larger crystals (Fig. 19a).
A magnified view of the both the coarse and fine areas can be seen in Figure 20a. The
major minerals of the sample were analyzed within each area. The garnets (Grt-3.dg.1 and Grt3.dg.2) were chemically similar and have an average composition of
Ca0.51Fe1.35Mg1.08Mn0.04Al1.98(Si3.00O12). The hornblende crystals, however, show a variation in
chemistry. Figure 21 shows the difference is weight percent between the oxides that compose the
hornblendes. The smaller hornblende (Hbl-3.dg.2) has more iron, silica and magnesium. The
larger hornblende (Hbl-3.dg.1) has more alumina, calcium, potassium, and titanium. The
plagioclase crystals (Pl-3.dg.1 and Pl-3.dg.2) had little difference in composition. The average
composition of the two plagioclase crystals is: K0.03Na0.58Ca0.41Al0.43(Al0.96Si2.57O8). The
orthopyroxene crystals (Opx-3.dg.1 and Opx-3.dg.2) show differences in composition. Figure 22
compares the chemical composition for each of the orthopyroxenes. The smaller orthopyroxene
(Opx-3.dg.2) has less magnesium and silica, but more calcium and alumina than the larger
orthopyroxene (Opx-3.dg.1).
Wet Meta-Gabbro
The wet amphibolite looks very different compared to the dry amphibolite (Fig. 19b).
The vesicles are much larger and cover a greater amount of space within the sample. The
vesicles can be seen in black in the BEI image of Figure 15b. The crystals are rounded to sub-
36
rounded. Overall the crystals within the wet amphibolite are about the same size as those of the
dry amphibolite.
A closer look at the sample shows that the crystals are less defined in some places (Fig.
20b). Many plagioclase crystals still have their original inclusions. Zoning occurs within some
hornblende crystals. The garnets analyzed (circled in Fig. 20b) have little variation in
composition. The average composition for the garnets of the wet amphibolite sample is:
Ca0.47Fe1.34Mg1.15Mn0.03Al2.02(Si2.97O12). The hornblende crystals of the sample also have very
similar compositions (Fig. 23). The biggest difference between the two crystals is the amount of
silica. The smaller hornblende crystal (Hbl-3.wa.2) has 1.92% more silica than the larger
hornblende (Hbl-3.wa.1). The plagioclase crystal analyzed (Pl-3.wa.1) has the composition:
K0.01Na0.58Ca0.43Al1.44Si2.55O8. An orthopyroxene was also chemically analyzed (Opx-3.wa.1) and
has the composition: Na0.03Ca0.02Fe0.54Mg1.34Al0.06(Al0.05Si1.95O6).
37
a.
b.
Figure 15. The two fine amphibolite samples from Experiment 3 held under 900°C and 8kbars at 65X
magnification. For each, the images on the left are BEI’s and the images on the right are SEI’s. (a) The dry
sample of the fine amphibolite. (b) The wet sample of the fine amphibolite with 12 weight percent water
added.
38
Pl
Hbl
Opx
Hbl
Pl
Hbl
Pl
Pl
Grt-3.da.2
Hbl
Pl
Opx
Grt
Hbl3.da.1
Grt
Hbl
Hbl
Hbl
Pl
Grt-3.da.1
Opx
Grt
Hbl
Pl
Grt
Opx
Pl
Opx
Opx
Grt
Grt
Grt
Pl
Hbl
Hbl-3.da.1
Hbl
Hbl
a.
Opx-3.da.1
Opx
Pl
Grt
Opx
Hbl
Pl
Opx
Hbl
Grt
Hbl
Pl
Pl
Grt
Hbl
Hbl
Opx3.wa,1
Hbl-L3.wa
Grt-3.wa.1
Hbl.3.wa.2
Hbl
a
L3.w
Grt-
Hbl
Pl-3.wa.1
Grt-L3.wa.2
Hbl.3.wa.1
Pl
Grt-3.wa.2
b.
Pl
Figure 16. Mineral identifications for the fine amphibolite samples put at 900°C
and 8kbars at 650X magnification as BEI’s. (a) The dry fine amphibolite
sample. (b) The wet fine amphibolite sample.
39
Grt-L3.wa
450
400
350
300
Mg
250
Counts
Al
Si
200
Ca
Mn
Fe
150
100
50
1
9
17
25
33
41
49
57
65
73
81
89
97
105
113
121
129
137
145
153
161
169
177
185
193
201
209
217
225
233
241
249
257
265
273
281
289
297
305
313
321
329
337
345
353
361
369
377
385
393
401
409
417
425
433
441
449
457
465
473
481
489
497
505
513
0
Distance From start of Line (um)
Figure 17. Chemical Profile of Grt-L3.wa. A cross section of a garnet from the wet metagabbro is chemically analyzed. The counts for each element is on the y-axis and the
distance in μm from the starting point of the line is on the x-axis.
Chemical Profile of Hbl-L3.wa
45
40
180
K
160
140
30
120
Counts
Counts
35
100
25
20
80
60
10
40
5
20
0
0
1
17
33
49
65
81
97
113
129
145
161
177
193
209
225
241
257
273
289
305
321
337
353
369
385
401
417
433
449
465
481
497
1
17
33
49
65
81
97
113
129
145
161
177
193
209
225
241
257
273
289
305
321
337
353
369
385
401
417
433
449
465
481
497
15
Distance From Start of Line (um)
160
140
Al
Mg
Distance From Start of Line (um)
180
160
Ca
140
120
120
Counts
100
Counts
100
80
80
60
60
40
40
20
0
0
1
17
33
49
65
81
97
113
129
145
161
177
193
209
225
241
257
273
289
305
321
337
353
369
385
401
417
433
449
465
481
497
1
17
33
49
65
81
97
113
129
145
161
177
193
209
225
241
257
273
289
305
321
337
353
369
385
401
417
433
449
465
481
497
20
Distance From Start of Line (um)
Distance From Start of Line (um)
Figure 18. Chemical Profile of Hbl-L3.wa. The variation of potassium, aluminum, magnesium, and
calcium across the hornblende crystal can be seen in the 4 graphs. The counts for each element is on
the y-axis and the distance in μm from the starting point of the line is on the x-axis.
40
a.
b.
Figure 19. The two fine meta-gabbro samples from Experiment 3held under 900°C and 8kbars at 65X
magnification. For each, the images on the left are BEI’s and the images on the right are SEI’s. (a) The dry
sample of the fine meta-gabbro. (b) The wet sample of the fine meta-gabbro with 15 weight percent water
added.
41
Hbl
Hbl-3.dg.2
Hbl
Grt-3.dg.2
Hbl
Hbl
Pl-3.dg.1
Pl-3.dg.2
Hbl
Opx
Hbl
Opx-3.dg.2
Opx-3.dg.1
Pl
Grt-3.dg1
Hbl-3.dg.1
Grt
a.
Pl
Pl
Grt
Pl
Grt-3.wg.1
Pl
Pl
Pl
Grt
Pl-3.wg.1
Pl
Hbl
Hbl-3.wg.1
Pl
Pl
Opx
Hbl-3.wg.2
Pl
Grt-3.wg.2
b.
Opx-3.wg.1
Pl
Hbl
Hbl
Pl
Pl
Pl
Hbl
Grt-3.wg.3
Pl
Figure 20. Mineral identifications for the fine meta-gabbro samples put at 900°C
and 8kbars at 650X magnification as BEI’s. (a) The dry fine meta-gabbro sample.
(b) The wet fine meta-gabbro sample.
42
Experiment 3: Dry Meta-Gabbro Hornblendes
50.00
Hbl-3.dg.1
45.00
Hbl-3.dg.2
40.00
Weight Percent
35.00
30.00
25.00
20.00
15.00
10.00
5.00
0.00
Na2O
MgO
Al2O3
SiO2
K2O
CaO
TiO2
MnO
FeO
Figure 21. Bar chart of the chemical analysis of hornblendes from the dry
meta-gabbro of Experiment 3. The weight percent oxide is the y-axis and the
different oxides are on the x-axis.
60.00
Experiment 3: Dry Meta-Gabbro
Orthopyroxenes
Opx-3.dg.1
50.00
Weight Percent
Opx-3.dg.2
40.00
30.00
20.00
10.00
0.00
Na2O
MgO
Al2O3
SiO2
K2O
CaO
TiO2
FeO
Figure 22. Bar chart of the chemical analysis of orthopyroxenes from the wet
meta-gabbro of Experiment 3. The weight percent oxide is the y-axis and the
different oxides are on the x-axis.
43
45.00
Experiment 3: Wet Meta-Gabbro Hornblendes
40.00
Weight Percent
35.00
30.00
Hbl-3.wg.1
25.00
Hbl-3.wg.2
20.00
15.00
10.00
5.00
0.00
Na2O MgO Al2O3 SiO2
K2O
CaO
TiO2
MnO
FeO
Figure 23. Bar chart of the chemical analysis of hornblendes from the wet
meta-gabbro of Experiment 3. The weight percent oxide is the y-axis and
the different oxides are on the x-axis.
44
Experiment 5: 800°C, 7kbars, 6 hours
For this run, amphibolite and meta-gabbro powders were heated to 800°C at 7 kbars. A
wet and dry sample of each rock type was made. The wet samples contained around 12 weight
percent of water added. The run lasted for 6 hours.
Dry Amphibolite
The dry amphibolite sample is composed of hornblende, plagioclase, garnet, and
orthopyroxene in decreasing order respectively. There are small vesicles dispersed throughout
the sample and they tend to occur mostly in plagioclase (Fig. 24a). The crystals are angular and
tend to range from 10 to 20µm in diameter.
Chemical analyses were completed for the crystals circled in Figure 25a. The average
garnet composition is: Ca0.31Fe1.45Mg1.19Mn0.04Al2.01(Si2.99O12). The two plagioclase crystals
analyzed have very similar compositions with less than 2
weight percent oxide difference for each oxide. The size
of the plagioclase crystals does not appear to be a factor in
composition. The average composition for plagioclase is:
Na0.53Ca0.47Al1.49Si2.48O8. The composition for the
hornblende crystal analyzed can be seen in Table 4.
Table 5. The composition of a hornblende from
the dry amphibolite sample of Experiment 5.
Wet Amphibolite
At first look in BEI, the wet amphibolite sample may not appear to be very texturally
different from the dry amphibolite (Fig. 24b). The wet amphibolite has much larger vesicles than
the dry amphibolite (Fig. 24). The vesicles are rounded and dispersed throughout the sample.
45
The wet amphibolite contains hornblende, plagioclase, and garnet in decreasing order
respectively. No orthopyroxene was found. The crystals are angular to sub-angular. Looking at
Figure the textural differences between the amphibolite samples can be seen clearly. The wet
amphibolite has larger, less angular crystals. The vesicles are distinct black holes (Fig. 25b).
Chemical analysis was completed on a number of crystals. A zoned hornblende was
analyzed in the center (Hbl-5.wa.1) and on the edge (Hbl-5.wa.1a). The compositions of all the
amphiboles analyzed within the wet amphibolite can be seen in Figure 26. The zoned amphibole
shows some slight difference between the edge and the center. The center of the amphibole has a
greater percentage of the oxides except for the amount of MgO. The greatest difference in
weight percent between the edge of the crystal and the center is 1.53% more calcium in the
center. Two other amphiboles were analyzed as well (Hbl-5.wa.3 and Hbl-5.wa.4). The largest
hornblende (Hbl-5.wa.1) has a greater weight percent of calcium, titanium, and potassium than
any of the other hornblendes analyzed. The hornblende crystal, Hbl-5.wa.4, appears to vary the
most from the other hornblende crystals as there are only to oxide for which it is not the
minimum or maximum.
Two garnet crystals were chemically analyzed (Grt-5.wa.1 and Grt-5.wa.2, Fig. 27). The
results can be seen in Figure. The two garnet crystals were chosen because of their differences in
shape. The narrow or thin garnet (Grt-5.wa.2) has a greater weight percent of every oxide except
for iron and manganese. The garnet, Grt-5.wa.1, has 1.31 weight percent more of iron and 0.62%
less magnesium than the narrow garnet. The garnets have some differences in composition, but
they are less than 2 weight percent differences in oxides. A good analysis of plagioclase was
unable to be obtained.
46
Dry Meta-Gabbro
The major minerals of the dry meta-gabbro sample are: hornblende, plagioclase, garnet,
and orthopyroxene in decreasing order respectively. A few crystals of apatite were found within
the sample. The samples had some vesicles all of which are less than 5 microns in diameter (Fig.
28a). The crystals are angular. Many crystals have rough, jagged edges.
A closer look at the sample in Figure 29a reveals the messy looking texture of the
crystals. The rough jagged edges can clearly be seen. No chemical zoning of crystals is apparent.
Garnets of the dry meta-gabbro sample were analyzed. The garnets were almost
chemically identical. The average garnet composition is: Ca0.48Fe1.38Mg1.09Mn0.04Al2.01(Si2.99O12).
The garnets in particular have jagged edges. One hornblende (Hbl-5.dg.1) was analyzed and
found to have the following composition:
K0.23Na0.63(Na0.22Ca1.78)(Fe1.30Mg2.88Ti0.18Al0.72)(Al1.93Si6.07)O22(OH)2.
Wet Meta-Gabbro
The wet meta-gabbro sample is very texturally different from the dry meta-gabbro
sample. The wet meta-gabbro sample has larger vesicles than the dry one as well as crystals with
sharper edges (Figs. 28 and 29). The sample generally has crystals around 20µm in diameter,
however there are some pockets of crystals around 5 to 10µm in diameter. Additionally no
orthopyroxene was found within the sample, there is an abundance of hornblende however.
A higher magnified view of the sample reveals the texture (Fig. 29b). Many crystals are
very well defined with smooth edges. Some edges are angular. No glass was found however
perfect form of some crystals could indicate the previous presence of a liquid.
47
Two garnet crystals were analyzed (Grt-5.wg.1 and Grt-5.wg.2). The smaller garnet (Grt5.wg.2) has almost 3% less iron than the larger garnet (Grt-5.wg.1). Their compositions are
similar overall. Two hornblende crystals were chemically analyzed. The smaller hornblende
(Hbl-5.wg.2) has 3% less calcium, 0.7% less iron, 1.1% less magnesium, and 0.6% less titanium
than the larger hornblende (Hbl-5.wg.1). The smaller hornblende does have 7.5% more silica and
2.0% more alumina than the larger garnet. The hornblendes of different sizes have different
compositions. This is likely because the hydration of orthopyroxene crystals would create a
crystal of a different composition.
48
a.
b.
Figure 24. The two fine amphibolite samples from Experiment 5 held under 800°C and 7kbars at 65X
magnification. For each, the images on the left are BEI’s and the images on the right are SEI’s. (a) The dry
sample of the fine amphibolite. (b) The wet sample of the fine amphibolite with 12.4 weight percent water
added.
49
Hbl
Pl
Hbl
Pl
Hbl
Grt
Grt
Opx5.da.1
Pl5.da.1
Opx
Grt
Grt-5.da.2
Hbl
Pl
Pl
Pl
Hbl-5.da.1
Grt
Hbl
Hbl
Opx
Grt
Grt
Pl
Pl5.da.1
Hbl
Pl
Opx
Grt-5.da.1
Opx
Hbl
a.
Grt-5.wa.1
Hbl-5.wa.1
Hbl5.wa.1a
Hbl
Grt-5.wa.2
Hbl
Hbl
Hbl-5.wa.4
Hbl
Hbl
Hbl-5.wa 3
Hbl
Hbl
Hbl
Hbl
Hbl
b.
Figure 25. Mineral identifications for the fine amphibolite samples put at
800°C and 7kbars at 650X magnification as BEI’s. (a) The dry fine
amphibolite sample. (b) The wet fine amphibolite sample.
50
Experiment 5: Wet Amphibolite
Hornblendes
45.00
40.00
Hbl-5.wa.1 (center)
Weight Percent Oxide
35.00
Hbl-5.wa.1a (edge)
Hbl-5.wa.3
30.00
Hbl-5.wa.4
25.00
20.00
15.00
10.00
5.00
0.00
Na2O
MgO
Al2O3
SiO2
K2O
CaO
TiO2
FeO
Figure 26. A chart of the compositions of hornblendes within the wet amphibolite
sample of Experiment 5 (800°C and 7kbars).
45.00
Experiment 5: Wet Amphibolite
Garnets
40.00
Grt-5.wa.1
Weight Percent Oxide
35.00
Grt-5.wa.2
30.00
25.00
20.00
15.00
10.00
5.00
0.00
MgO
Al2O3
SiO2
CaO
MnO
FeO
Figure 27. A chart of the compositions of garnets within the wet amphibolite sample
of Experiment 5 (800°C and 7kbars).
51
a.
b.
Figure 28. The two fine meta-gabbro samples from Experiment 5 held under 800°C and 7kbars at 65X
magnification. For each, the images on the left are BEI’s and the images on the right are SEI’s. (a) The dry
sample of the fine meta-gabbro. (b) The wet sample of the fine meta-gabbro with 15 weight percent water
added.
52
Pl
Hbl
Opx
Hbl
Grt
Pl
Hbl
Hbl-5.dg.1
Grt-5.dg.2
Opx
Ap
Hbl
Grt-5.dg.1
Grt
Pl5.dg.1
Opx
Opx
Opx
Hbl
a.
Grt-5.wg.2
Hbl-5.wg.1
Grt
Grt
Hbl
Grt
Grt-5.wg.1
Hbl-5.wg.2
b.
Figure 29. Mineral identifications for the fine meta-gabbro samples put at
800°C and 7kbars at 650X magnification as BEI’s. (a) The dry fine metagabbro sample. (b) The wet fine meta-gabbro sample.
53
Experiment 6: 800°C, 5kb, 2 days 21 hours
This experiment consisted of two samples of amphibolite (GM-407) and two samples of
meta-gabbro (GM-307). One sample of amphibolite was dry and the other had 6% water added.
The meta-gabbro samples consisted of a dry sample and a sample with 7.2% water added. The
run lasted for about 45 hours and had a stable temperature and pressure throughout.
Dry Amphibolite:
The dry amphibolite sample has small vesicles that appear to prefer occurring around and
within plagioclase crystals; however there are vesicles within other minerals (Fig. 30a). The
crystals range in size from less than 2 µm to greater than 50 µm. Hornblende is the most
abundant mineral. Plagioclase, garnet, and orthopyroxene are also present and listed in order of
abundance respectively. Fractures occur within every mineral type. In general, the crystals are
angular to sub-angular (Fig. 30a).
Figure 31a is an image of the dry amphibolite sample with a large garnet crystal (Grt6.da.1). The garnet crystal edges appear to have been affected by the experiment. The edges are
rough and wavy. The crystal is not as angular as many of the crystals around it. Figure 32 shows
the counts of various elements over the line labeled in Figure 31a. The garnet is homogenous,
there is variation but that occurs after 480µm, which is no longer on the garnet crystal. A
chemical analysis of the same garnet was obtained formula for the garnet labeled Grt-6.da.1 in
Figure 31a is: Ca0.39Fe1.36Mg1.20Mn0.04Al2.00(Si2.98O12).
Two different plagioclase crystals were chemically analyzed, shown in Figure 31a as Pl6.da.1 and Pl-6.da.2. It is clear that there are two distinct plagioclase types within the altered dry
amphibolite. Pl-6.da.2 has 2% more sodium and more than 4% less calcium than Pl-6.da.1. Also,
54
the aluminum to silica ratio is 1:1.37 in Pl-6.da.1 and 1:1.77 in Pl-6.da.2. Both plagioclases are
close to anorthite in composition.
Wet Amphibolite:
The wet amphibolite contains many more vesicles than the dry amphibolite (Fig. 30b).
The vesicles are also larger within the wet amphibolite. There are pockets of small crystals (~5
µm) within the majority of larger crystals (~30 µm). The crystals are angular and sub-angular.
The edges of crystals have a rough zigzagging pattern (Fig. 30b). Hornblende was most
abundant with plagioclase, garnet and orthopyroxene following respectively.
Figure 31b shows the wet amphibolite with mineral identification labels. The wide range
of crystal size can be seen even clearer in Figure 31b along with the zigzagging crystal edges. A
chemical analysis was done for the plagioclase crystals Pl-6.wa.1 and Pl-6.wa.2 (Table 5). They
are very similar to each other. The plagioclase crystals are less than 1% different in the
compound percent of sodium. The aluminum to silica ratio is 1:1.83 in Pl-6.wa.1 and 1:1.78 in
Pl-6.wa.2. The plagioclase crystals are both anorthitic.
Dry Meta-Gabbro
The dry meta-gabbro has small rounded vesicles (Fig. 33a). They are dispersed randomly
throughout the sample. The crystals are angular and sub angular and range in size from 3µm to
60µm. Plagioclase and orthopyroxene are the dominant minerals followed by hornblende and
then garnet.
55
A strange texture occurs within the dry meta-gabbro sample. The crystals look altered on
their edges as they have very irregular boundaries. Also the smaller crystals are not sharply
defined.
The chemistry of the two different garnets circled in Figure 34a, Grt.6.dg.1 and Grt6.dg.2, was obtained. The larger garnet, Grt-6.dg.1, has 1.177 weight percent more of Al2O3,
1.143 weight percent more of FeO, and 2.303 weight percent less of SiO2 than Grt-6.dg.2. The
differences between the two garnets are not large.
The two hornblende crystals circled in Figure 34a, Hbl-6.dg.1 and Hbl-6.dg.2, were also
chemically analyzed (Table 6). Each crystal has a distinct texture. Hbl-6.dg.1 has 6.7% more
weight percent of SiO2 than Hbl- 7.dg.2. Additionally, Hbl-6.dg.1 has more aluminum, calcium,
manganese, and sodium than the other hornblende. Hbl-6.dg.2 has a greater amount of iron,
magnesium, titanium, and potassium than Hbl-6.dg.1. The orthopyroxene crystal, Opx-6.dg.1, is
richer in magnesium than in iron. Its chemical formula is
Na0.03Ca0.02Fe0.58Mg1.35Al0.04(Al0.06Si1.94O6).
Wet meta-gabbro
Comparing the dry meta-gabbro to the wet-meta-gabbro it is clear that the vesicles are
much larger in the wet meta-gabbro (Fig. 33b). Hornblende is the most abundant mineral
followed by plagioclase and then orthopyroxene, which occurs only in minor amounts. No garnet
was found within the random areas analyzed. It appears that the meta-gabbro has converted into
an amphibolite. The crystal edges are smooth and not very angular.
A close up of the wet-gabbro sample can be seen in Figure 34b. The holes occur
primarily around crystal boundaries and within plagioclase. The largest crystals are hornblende.
56
A small crystal of orthopyroxene can be seen with the majority of its edges in contact with
hornblende (Opx-6.wg.1). There is little if any defined zoning within crystals of the wet metagabbro. A chemical analysis profile of a hornblende crystal (Hbl-6.wg.1) was completed and is
indicated in Figure 34b. The results of the analysis can be seen in Figure 35. The beginning of
the line does not begin on the hornblende crystal, but rather on a hole adjacent to it. The analysis
goes from left to right. The hornblende crystal shows a change in chemistry at the upper right
corner. At the end of the line there is an increase in silica and aluminum. Additionally, there is a
decrease in calcium and magnesium. At the beginning of the profile, calcium and iron are
roughly equal in amount. Then calcium increases while iron decreases, then both come back to
close to where they started in the middle of the crystal. This pattern occurs once more in the
second half of the crystal.
57
a.
b.
Figure 30. The two fine amphibolite samples from Experiment 6 held under 800°C and 5kbars at 650X
magnification. For each, the images on the left are BEI’s and the images on the right are SEI’s. (a) The dry
sample of the fine amphibolite. (b) The wet sample of the fine amphibolite with 6 weight percent water
added.
58
Opx
Pl
Pl
Hbl
Pl-6.da.1
Pl
Opx
ine
tL
rne
Ga
Pl-6.da.2
Grt-6.da.1
Hbl-6.da.1
Opx
Hbl
a.
Pl
Hbl
Pl-6.wa.1
Pl
Hbl
Hbl
Hbl
Opx
Pl-6.wa.2
Hbl
Opx
Pl
Hbl
Hbl
Hbl
Pl
Hbl
Grt
Hbl
Grt
b.
Pl
Figure 31. Mineral identifications for the fine amphibolite samples put at
800°C and 5kbars at 2000X magnification as BEI’s. (a) The dry fine
amphibolite sample. (b) The wet fine amphibolite sample.
59
Figure 32. A chemical profile of a large garnet from the dry amphoblite sample of Experiment 6.
The garnet is homogenous.
Pl-6.wa.1
Pl-6.wa.2
Compound % Nos. of ions Compound % Nos. of ions
Na2O
6.88
0.61
6.17
0.55
MgO
0.12
0.01
1.06
0.07
Al2O3
26.29
1.41
25.97
1.41
SiO2
56.66
2.58
54.39
2.51
K2O
0.28
0.02
0.12
0.01
CaO
8.03
0.39
9.07
0.45
TiO2
-0.03
0.00
0.06
0.00
MnO
0.08
0.00
-0.02
0.00
FeO
0.26
0.01
1.37
0.05
8.00
8.00
98.57
5.03
98.20
5.06
Table 6. Two plagioclase compositions from the wet amphibolite sample of Experiment 6.
60
a.
b.
Figure 33. The two fine meta-gabbro samples from Experiment 6 held under 800°C and 5kbars at 650X
magnification. For each, the images on the left are BEI’s and the images on the right are SEI’s. (a) The dry
sample of the fine meta-gabbro. (b) The wet sample of the fine meta-gabbro with 15 weight percent water
added.
61
Opx
Opx
Opx-6.dg.1
Pl
Opx
Hbl
Opx
Hbl
Hbl
Hbl-6.dg.2
Grt-6.dg.2
Hbl-6.dg.1
Pl
Grt-6.dg.1
Opx
Hbl
Pl
a.
Hbl
Pl
Hbl-6.wg.1
Line
Hbl
1
Hbl
Pl
Hbl
Hbl
Hbl-6.wg.3
Pl
Hbl
Hbl
Pl
Pl
Opx-6.wg.1
Hbl-6.wg.2
Hbl
Hbl
Pl
Hbl
Hbl
Hbl-6.wg.4
Hbl
b.
Figure 34. Mineral identifications for the fine meta-gabbro samples put at
800°C and 5kbars at 2000X magnification as BEI’s. (a) The dry fine metagabbro sample. (b) The wet fine meta-gabbro sample.
62
Hbl-6.dg.1
Hbl-6.dg.2
Compound % Nos. of ions Compound % Nos. of ions
Na2O
3.28
0.86
2.67
0.74
MgO
9.46
1.90
12.97
2.76
Al2O3
21.00
3.34
15.85
2.67
SiO2
48.47
6.54
41.78
5.97
K2O
0.35
0.06
3.14
0.57
CaO
9.62
1.39
9.04
1.38
TiO2
0.17
0.02
3.68
0.39
MnO
0.23
0.03
0.05
0.01
FeO
9.71
1.10
12.32
1.47
23.00
23.00
102.28
15.23
101.51
15.96
Table 7. Hornblende compositions of the dry metagabbro sample of Experiment 6.
Figure 35. A chemical profile of a hornblende crystal from the wet meta-gabbro sample of Experiment 6.
63
Experiment 7: 800°C, 6kb, 4 days
Two different rock types were used in this experiment: amphibolite and meta-gabbro. For
each type, a dry sample was used along with one with water added to it. Around 18-19% weight
percent water was added to increase the amount of melt formed in the run. The samples were
held at 800°C and 6kb for 4 days.
Dry Amphibolite
The amphibolite remained predominately composed of hornblende after the run.
Plagioclase and garnet are the next most abundant, followed by orthopyroxene. The crystals are
fairly uniform in size (~20µm) and are angular to sub-angular (Fig. 36a). In SEI, there do appear
to be some vesicles within the sample, but they are very small (<5µm).
A closer look at the dry amphibolite shows the rough crystal edges that are not present
within the starting material (Fig. 37a). It appears as if the minerals are being dissolved or broken
down during the run. The plagioclase crystals have holes within them. Holes also appear around
crystal edges. There may be zonation in plagioclase crystals, but the majority of crystals have no
zonation. When looking at Figure 37a the edges of some crystals appear lighter but it is likely
due to edge effects in backscatter electron imaging and not due to growth because of the texture
of the edges. The two garnets analyzed in Figure 37a (Grt-7.da.2 and Grt-7.da.3) have similar
compositions with differences in elements of only 3 weight percent (Bartolome)maximum. Thus,
despite the size difference between the two garnets, they have the same composition. The two
hornblende crystals circled (Hbl-7.da.2 andHbl-7.da.3) also have similar compositions with the
largest difference in weight percent of an element being only 1.14%.
64
Wet Amphibolite
The wet amphibolite looks very different from the dry amphibolite. The most noticeable
difference is the amount garnet is less within the wet amphibolite. Only a small number of
rounded garnets remain (Fig. 36b). The texture of the wet amphibolite is also very different.
Larger round vesicles are spread throughout the sample. The crystals within the wet amphibolite
typically have rounded edges. In some places it appears as if new crystals have formed within a
melt, as the crystals show perfect forms. No orthopyroxene was found, leading to the conclusion
that the original orthopyroxene was hydrated and formed amphibole. Hornblende is the most
abundant mineral, followed by plagioclase. Once again, garnet is present, but in small amounts.
The three garnets analyzed in Figure 37b all had similar compositions. The average
composition for the garnets within the wet amphibolite can be found in Table 7. Three
hornblende crystals were also analyzed (Fig. 37b and Table 8). There is some significant
variation within the composition of the hornblende crystals. The smallest hornblende analyzed,
Hbl-7.wa.3, has 7.49 less weight percent CaO than the larger Hbl-7.wa.1 and 4.71 less weight
percent CaO than Hbl-7.wa.2. While Hbl-7.wa.3 has less calcium than the larger hornblende
crystals, it has a greater amount of magnesium and iron. Hbl-7.wa.3 has 3.44 weight percent
more FeO than Hbl-7.wa.1 and 1.88 weight percent more FeO than Hbl-7.wa.2. Additionally, it
has 2.44 and 1.05 weight percent more MgO than Hbl-7.wa.1 and Hbl-7.wa.2 respectively. The
plagioclase crystal, Pl-7.wa.1, shown in Figure B2b, has the composition;
K0.01Na0.42Ca0.57(Al1.60Si2.40)O8.
One hornblende crystal (Hbl-7.wa.1) was analyzed across a section of itself, to see if it
contained any chemical zoning (Fig. 37b). The results show a decrease in calcium and
magnesium in the rims of the hornblende crystal. Potassium has the opposite trend, with higher
65
counts within the rims and lower counts within the center. A garnet (Grt-7.wa.1) was also
analyzed along a cross section (Fig. 37b and Fig. 38). The garnet did have a decrease in iron and
an increase in silica along its edges. There is also a decrease in magnesium along the edge,
however it is a smaller change compared to those stated above.
Dry Meta-Gabbro
The dry meta-gabbro contains a larger amount of hornblende than originally. It still
contains orthopyroxene in significant amounts. Plagioclase is the second most common mineral.
Garnet occurs in small amounts. A single crystal of olivine was found. There are two distinct
crystals sizes. The majority is a larger size around 10 µm, but there are pockets of smaller
crystals within the sample (Fig. 39a and Fig. 40b). Small vesicles are scattered throughout the
meta-gabbro, they do appear to occur less abundantly within the smaller crystal size areas,
however this could be due to a smaller size of vesicle (Fig. 39a).
The compositions of all the hornblendes analyzed within the dry meta-gabbro can be seen
in Figure 41. There are only a few percent differences between the hornblendes. There does not
appear to be a difference in composition between the larger crystals and the smaller crystals. The
garnets analyzed within the dry meta-gabbro had very similar compositions with an average
composition of: Ca0.49Fe1.27Mg1.08Mn0.03Al2.00(Al0.01Si2.99O12).
A hornblende crystal (Hbl-7.dg.5) was analyzed to determine if chemical zonation
occurred within it. There is a slight increase in the amount of potassium and calcium in the center
of the crystal. Magnesium increases by greater amounts towards the center of the crystal. A
second line scan was done across a garnet crystal (Grt-L7-dg). The garnet was found to have
sight zoning, specifically the amount of magnesium and iron increased toward the center of the
crystal.
66
Wet Meta-Gabbro
The wet meta-gabbro looks texturally similar to the dry meta-gabbro (Fig. 39b). Like the
dry version, it has a majority of crystals around 10µm with pockets of smaller crystals. It does
however have a greater number of vesicles. The crystals are slight more rounded within the wet
meta-gabbro. The wet meta-gabbro contains hornblende, plagioclase, orthopyroxene, and garnet
in decreasing amounts respectively. The orthopyroxene tends to be smaller than the hornblende.
Chemical analysis of the garnets within the fine pockets and the coarser areas were
completed. The smaller garnets have 1.99% less weight percent FeO than the larger garnets
(Table 9). Overall the garnets are very similar in composition, thus crystal size does not appear to
be a factor in composition of garnet within this sample. The hornblende crystals of the wet metagabbro have very similar compositions to each other as well as similar compositions to the
hornblende crystals of the dry meta-gabbro (Fig. 42).
A chemical analysis was done across a hornblende crystal (Hbl-7.wg.1) showing some
differences between the center of the crystal and the edges. Specifically, potassium, titanium, and
calcium increase towards the center of the crystal. Iron decreases slightly in the interior of the
crystal. A chemical analysis cross-section of a garnet (Grt-7.wg.2) has some patterns within it.
Iron increases towards the center of the garnet. Also, at the start of the line magnesium was at its
lowest concentration and calcium was at its highest concentration. At the end of the line the
opposite is true, magnesium had increased and calcium has decreased.
67
a.
b.
Figure 36. The two fine amphibolite samples from Experiment 7 held under 800°C and 6kbars at 65X
magnification. For each, the images on the left are BEI’s and the images on the right are SEI’s. (a) The dry
sample of the fine amphibolite. (b) The wet sample of the fine amphibolite with 19 weight percent water
added.
68
Hbl
Pl
Hbl
Pl
Hbl
Hbl
Hbl
Grt-7.da.3
Opx
Hbl
Grt
Grt
Grt
Opx
Grt
Hbl
Hbl
Hbl
Pl
Grt
Grt-7.da.2
Hbl-7.da.3
Opx-7.da.2
Hbl-7.da.2
Hbl
Opx
Pl
a.
Hbl
Pl
Hbl
Hbl-7.wa.2
Grt-7.wa.2
Hbl
Pl
Hb
l-L
.7.
wa
Hbl-7.wa.1
Pl
Hbl
Pl
Hbl
Hbl
Pl
Hbl
Grt-7.wa.1
Grt-L 7.wa
Pl-7.wa.1
Pl
Hbl
Hbl
Grt-7.wa.3
Pl
Hbl
Pl
b.
Hbl-7.wa.3
Hbl
Figure 37. Mineral identifications for the fine amphibolite samples put at
800°C and 7kbars at 2000X magnification as BEI’s. (a) The dry fine
amphibolite sample. (b) The wet fine amphibolite sample.
69
Average
Average
Grt-7.wa Compound
Nos. of Ions
Percent
MgO
Al2O3
SiO2
CaO
TiO2
MnO
FeO
O
Total
11.25
22.85
40.38
3.99
0.05
0.58
22.17
1.25
2.00
3.00
0.32
0.00
0.04
1.38
12
101.27
7.99
Table 8. The average composition of garnets
from the wet amphibolite of Experiment 7.
Hbl-7.wa.1
Hbl-7.wa.2
Hbl-7.wa.3
Compound % Nos. of ions Compound % Nos. of ions Compound % Nos. of ions
Na2O
3.24
0.90
2.84
0.79
2.66
0.72
MgO
13.13
2.80
14.51
3.09
15.56
3.26
Al2O3
15.91
2.68
15.91
2.68
17.30
2.87
SiO2
42.74
6.12
43.82
6.26
45.08
6.34
K2O
0.95
0.17
0.38
0.07
0.09
0.02
CaO
11.23
1.72
8.44
1.29
3.74
0.56
TiO2
1.49
0.16
0.58
0.06
0.33
0.03
MnO
0.06
0.01
0.07
0.01
0.13
0.02
FeO
11.23
1.34
12.79
1.53
14.67
1.73
23.00
23.00
23.00
Table 9. Three hornblende compositions from the wet amphibolite of Experiment 7.
Figure 38. A chemical profile of a garnet from the wet amphibolite sample of Experiment 7. See Figure 37b for an
image of the line profiled.
70
a.
b.
Figure 39. The two fine meta-gabbro samples from Experiment 7 held under 800°C and 6kbars at 65X
magnification. For each, the images on the left are BEI’s and the images on the right are SEI’s. (a) The dry
sample of the fine meta-gabbro. (b) The wet sample of the fine meta-gabbro with 18 weight percent water
added.
71
Pl
Opx
Hbl
Hbl
Opx
Opx
Opx
Hbl
.dg
Hbl L7
Hbl
Opx
Hbl
Pl
Grt
Hbl 7 dg 5
Pl
Pl
Hbl
Opx
Hbl 7 dg 1
Hbl
Grt
Hbl 7 dg 3
Pl
Pl
Pl
Pl
Ol 7 dg 1
Pl
Opx
Grt
Hbl
Hbl 7 dg 2
Grt 7 dg 1
Pl
Opx
Hbl 7 dg 4
Hbl
Pl
Grt
Hbl
Gr
a.
7
tL
Hbl
Pl
dg
Hbl
Opx
Pl
Opx
Opx
Hbl
Pl
Hbl
Grt
Hbl 7 wg 6
Grt 7 wg 1
Hbl
Pl
Pl
Pl
Oxide
Pl
7.w
g
Opx
Grt 7 wg 3
Gr
tL
Hbl
Grt 7 wg 2
Pl
Hbl 7 wg 2
Opx
Hbl
Hbl
Hbl
xL
Op
Hbl
Hbl
Opx
Opx
Hbl 7 wg 3
Opx
Hbl 7 wg 5
Opx
Opx
Hbl
Hbl
Grt
Hbl
Pl
Hbl 7 wg 1
Opx
Hbl 7 wg 4
g
7.w
lL
Hb
Pl
b.
Grt
Pl
Grt
Opx
Pl
Opx
Opx
Pl
Pl
Hbl
Pl
Grt 7 wg 4
Pl
Hbl
Pl
Pl
Grt
Opx
Pl
g
7.w
Hbl
Hbl
Hbl
Pl
Hbl
Pl
Hbl
Opx
Pl
Hbl
Grt
Hbl
Figure 40. Mineral identifications for the fine meta-gabbro samples put at 800°C and 6kbars at 2000X magnification as BEI’s. (a) The dry fine meta-gabbro sample with the coarse area on the left and the fine area on the
right. (b) The wet fine meta-gabbro sample with the coarse area on the left and the fine area on the right.
72
Experiment 7: Dry Meta-Gabbro Hornblendes
50.000
45.000
40.000
Weight Percent
35.000
30.000
Hbl-7.dg.1
Hbl-7.dg.2
25.000
Hbl-7.dg.3
Hbl-7.dg.4
20.000
Hbl-7.dg.5
15.000
10.000
5.000
0.000
Na2O
MgO
Al2O3
SiO2
K2O
CaO
TiO2
FeO
Figure 41. Compositions of hornblendes in weight percent oxide from the dry metagabbro of Experiment 7.
Experiment 7: Wet Meta-Gabbro Hornblendes
50
45
40
Weight Percent
35
30
Hbl-7.wg.1
Hbl-7.wg.2
25
Hbl-7.wg.3
Hbl-7.wg.4
Hbl-7.wg.5
20
Hbl-7.wg.6
15
10
5
0
Na2O
MgO
Al2O3
SiO2
K2O
CaO
TiO2
FeO
Figure 42. Compositions of hornblendes in weight percent oxide from the wet metagabbro of Experiment 7.
73
Table 10. Garnet compositions of different size crystals within the wet meta-gabbro of
Experiment 7.
74
Discussion
The garnets of the meta-gabbro samples and the amphibolite samples plot in two different
groups on a ternary diagram (Fig. 43). This shows that the meta-gabbros did not equilibrate to
the amphibolite under the temperature and pressure conditions applied. While the wet metagabbros hydrated and became amphibolites, their garnets did not have the same composition as
the garnets from the amphibolite samples. Thus, the simple addition of water to the meta-gabbro
did not create the same amphibolite seen at Gore Mountain. No melt was found within the
samples also indicating that partial melting is unlikely to be involved in the formation of the
garnet ore. The large vesicles in the wet samples indicate some vapor phase present. A water
vapor is likely to form due to oversaturation of water within the powder.
When the garnets of the experiment samples are compared to garnets of previous studied,
specifically Luther (1976) and Levin (1950), there is little compositional difference (Fig. 43).
The garnets from the meta-gabbros of Levin (1950) plot with the garnets of the experimental
samples. The same occurs with the garnets from the amphibolite samples. The cores of Luther’s
(1976) amphibolite garnets plot with the garnets of the experimental amphibolite samples. This
implies that the conditions of the experiments did not alter the composition of the garnets (the
original material).
There are two garnets that appear to be outliers. Both are from Experiment 2 (800°C and
8kb). The outliers are from the fine wet amphibolite sample. The garnet that plots with the metagabbros is likely a rim of a larger garnet, as the rims of the natural amphibolite plot closer to the
meta-gabbro (Luther, 1976). No explanation is known for the outlier that is very magnesium
rich.
75
The hornblende of both the meta-gabbros and the amphibolites do not show any pattern
(Fig. 44). The hornblendes of the original powder plot within the small cloud of points. One
hornblende form Luther (1976) was plotted and also graphs near the experimental hornblende
samples. While zoning and growth appeared in many hornblende crystals, the centers of the
hornblende crystals appear not to have changed much or at all in composition.
Two pairs of hornblende centers and edges are shown in Figure with an arrow pointing to
the edge of the crystals. The hornblende pair of the wet meta-gabbro from Experiment 1, appears
to have changed very much in composition, yet the edge still plots among all of the hornblendes
graphed. The edge of the hornblende crystal in Experiment 5 has not changed very much at all.
Thus, the hornblendes do not appear to have changed in composition because of the experiments.
This is significant because it supports the results of the garnet compositions, specifically that the
powders did not appear to reorganize chemically during the experiments.
The wet amphibolite sample from Experiment 3 showed the greatest amount of growth.
This could be due to the greater temperature than other runs. Wolf and Wyllie (1993) reported
that garnets grew up to 100µm after 4 days at 925°C and 10 kbars. Experiment 3 also lasted the
longest, 6 days and 3 hours. It is possible that the experiments needed longer durations, however
the lower pressure of the experiments completed in this study should have allowed faster
diffusion. Wolf and Wyllie (1993) also state that garnets began to nucleate at 850°C. They did
start out with a garnet free powder. With garnet crystals already in the powder able to act as seed
in addition to lower pressures, it would seem likely that melting and garnet growth would have
occurred in greater amounts in the experiments of this study. Another factor is the addition of
water. This in itself could have aided the growth of crystals. Additionally, the grinding of the
rock into a powder takes the crystals out of textural equilibrium. Growth could have occurred
76
because of changes in surface energy. Many factors aided the growth of the minerals, yet the two
unique ones for this sample appear to be the higher temperature and the longer duration of the
experiment.
Melt was not texturally observed in the BEI images. There were no chemical analyses
that did not match reasonable mineral compositions. Additionally, using EBSD at Amherst
College, amorphous areas were looked for within samples, yet none were identified. It is possible
that the melt could have move to a different part of the sample that was not analyzed. Minerals
were consumed in some experiments and grown in others, however, no glass was apparent in any
of the samples. Using the program MELTS, a liquid was predicated to form at similar conditions.
MELTS did not predict the formation of hornblende in most of the cases, but rather
clinopyroxene. This difference could have changed the predicted outcomes. Additionally,
vesicles indicate a fluid or vapor phase did exist within the sample. The amount of water added
to the experiments should have been enough to saturate the sample, allowing for a separate water
phase. The presence of vesicles also indicates that the gold capsule was sealed during the
experiment and that melt could not have escaped.
This study did not replicate the results of a previous experiment done with the same Gore
Mountain samples. Howard (2004) ran an experiment using the same setup. She put the same
meta-gabbro and amphibolite, one wet and one dry, at 800°C and 8kb. The wet samples had 20
weight percent water added to them. Although garnets did not grow, the wet amphibolite sample
had a significant, visible amount of glass after the run. It is not clear why the results varied so
greatly. This study put a maximum of 18 weight percent water and no glass was evident. Howard
(2004) calculated the weight percent water using the volume of the cylinder. This is not the best
approach because the cylinders vary in volume. This study used the actual weight of the water
77
compared to the weight of the powder added to determine the weight percent of water added.
The results of this study were consistent, as no melt appears to have formed in any of the
experiments. It is also not an ideal to compare the results with only one example.
This study shows what conditions were unfavorable for garnet growth. Specifically, The
addition of 18 weight percent water to the amphibolite at 800°C and 6kb dissolved the majority
of the garnet within the sample. The addition of water to the meta-gabbro at 800°C and 5kb
(Exp. 6) also dissolved the garnet within the sample. Low pressures were used because they
favored the formation of a partial melt, but this did not support the growth of garnet in the abovementioned conditions. The fact that it appears that no melt has formed under conditions similar
those thought to have occurred at Gore Mountain, does not support the idea that a partial melt
aided the growth of the garnets
78
Garnets from the Wet and Amphibolites
Ca
Wet
Meta-Gabbro
Wet
Amphibolite
Dry
Meta-Gabbro
Exp. 1
Exp. 1
Exp. 3
Exp. 3
Exp. 6
Exp. 7
Exp. 7
Exp. 2
Exp. 3
Exp. 5
Exp. 7
Dry
Amphibolite
Exp. 2
Exp. 3
Exp. 5
Exp. 6
Exp. 7
Amphibolite Ore
from Luther (1976)
Meta- Gabbro from
Levin (1950)
Original MetaGabbro Powder
Core
Original
Amphibolite
Powder
Mg
Fe
e
400X
Figure 43. A ternary plot of the composition of garnets from different experiments done with meta-gabbro and amphibolite powders from Gore Mountain.
The samples with water added are shown as solid circles (meta-gabbro) or as
solid squares (amphibolite) . The dry samples are shown as hollow circles
(meta-gabbro) or as hollow squares (amphibolite). The same color denotes the
same temperature and pressure conditions. Notice the how the two different
rock types plot as two separate groups overall. Also note how the garnet compositions did not change from the original material.
79
Rim
Hornblende Composition Variation
0.36
Uncooked
Exp. 3-Dry
Exp. 5-Dry
Exp. 6-Dry
Exp. 7-Dry
Exp. 1-Wet
Exp. 3-Wet
Exp. 5-Wet
Exp. 6-Wet
Exp. 7-Wet
Luther (1976)
Uncooked
Exp. 3-Dry
Exp. 5-Dry
Exp. 7-Dry
Exp. 3-Wet
Exp. 5-Wet
Exp. 7-Wet
0.34
0.32
Al(Al+Si)
0.3
0.28
0.26
0.24
0.22
0.2
0.62
0.64
0.66
0.68
Mg/(Mg+Fe)
0.7
0.72
0.74
Figure 44. Graph of the molar ratio of elements within hornblende crystals. This graph shows the variation of composition
of hornblendes within wet and dry meta-gabbro and amphibolite samples. Hornblendes from the original dry unaltered
powders are plotted . An analysis of a hornblende found in Luther (1976) is also compared. The samples with water added
are shown as solid circles (meta-gabbro) or as solid squares (amphibolite) . The dry samples are shown as hollow circles
(meta-gabbro) or as hollow squares (amphibolite). The same color denotes the same temperature and pressure conditions.
The hornblende compositions are very similar in both meta-gabbro and amphibolite samples.
80
Conclusions
The goal of this study was to determine if the presence of a partial melt was a factor in
the formation of the large garnets at Gore Mountain. The results do not support the hypothesis
that the garnets grew in the presence of a partial melt. Additionally, the simple addition of water
did not change the meta-gabbro into the garnet amphibolite Conditions were found which
disfavored the growth of garnets (low pressure, high water content). One particular conditions
was found which favored the growth of crystals, specifically, adding water to the amphibolite
and placing it at 900°C and 8kbars, however, the growth was not in the presence of a melt and
could have been due to surface energy changes causing the large crystals to grow and the smaller
crystals to disappear. The conditions for the formation of the large garnets are yet to be
determined.
81
References
Asimow, P., Ghiorso, M. Algorithmic Modifications Extending MELTS to Calculate Subsolidus
Phase Relations. American Mineralogist 83 (1998): 1127-1131
Ayers, J., J. Brenan, B. Watson, D. Wark, and W. Minarik. "A new capsule trechnique for
hydrothermal experiments using the piston-cylinder apparatus." American Mineralogist 77
(1992): 1080-1086.
Bartolome, P. "Genesis of the Gorw Mountain Garnet Deposit, New York." Economic Geology
and the Bulletin of the Society of Economic Geologists (The Economic Geology Publishing
Company), 1960: 255-277.
Ghiorso, M., Sack, R. Chemical Mass Transfer in Magmatic Processes. IV. A Revised and
Internally Consistent Thermodynamic Model for the Interpolation and Extrapolation of LiquidSolid Equilibria in Magmatic Systems at Elevated Temperatures and Pressures. Contributions to
Mineralogy and Petrology 119 (1995):197-212 (MELTS)
Goldblum, D., and M. Hill. "Enhanced Fluid Flow Resulting from Competency Contrast Within
a Shear Zone; the Garnet Ore ZOne at Gore Mountain, NY." Journal of Geology (The University
of Chicago Press) 100, no. 1 (1992): 776-782.
Howard, H. Effect of Partial Melt on the Growth of Gore Mountain Garnets. Special Studies,
Geosciences, Smith College, unpublished, 2004.
Levin, S. "Genesis of Some Adirondack Garnet Deposits." Bulletin of the Geological Society of
America 61 (1950): 519-565.
Luther, F. A chemical reaction for the formation of the Gore Mountain garnet deposit, Warren
County, New York. Ph.D. Dissertaion, Lehigh Univeristy, unpublished, 1976.
McLelland, J. "Geochronology and petrogenesis of Adirondack igneous and metamorphic
rocks." Field Trip Guide for the 76th Annual Meeting of the New York State Geological
Association, 1995: 205-226.
Morse, S., J. Brady, and B. Sporleder. "Experimental Petrology of the Kiglapait Intrusion:
Cotectic Trace for the Lower Zone at 5 kbar in Graphite." Journal of Petrology 45, no. 11 (2004):
2225-2259.
Wolf, M., and P. Wyllie. "Dehydration-melting of amphibolite at 10 kbar: the effects of
temperature and time." Comtributions to Mineralogy and Petrology, 1994: 369-383.
Wolf, M., and P. Wyllie. "Garnet growth during amphibolite anatexis: implications of a
garnetiferous restite." Journal of Geology 101 (1993): 357-373.
82
Appendix I: Additional Run Information
Experiment 1
Sample 1
Sample 2
Sample 3
Sample 4
10/22/10
Time
5:38:00 PM
5:39:00 PM
5:39:40 PM
5:47:00 PM
5:57:00 PM
6:10:00 PM
6:37:00 PM
7:00:00 PM
8:09:00 PM
8:38:00 PM
10:09:00 PM
10:30:00 PM
11:48:00 PM
9:09:00 AM
10:07:00 AM
12:50:00 PM
5:37:00 PM
8:17:00 PM
8:19:00 PM
8:24:00 PM
10:27:00 PM
9:00:00 AM
11:20:00 AM
12:03:00 PM
1:42:00 PM
1:56:00 PM
1:57:00 PM
2:42:00 PM
Powder Sample
GM-307
GM-308
GM-307
GM-308
Temperature
18
100
200
300
400
500
600
700
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
Powder Wt (g) Water Wt (g)
Wt% H20
0.025
0.0000
0.022
0.0000
0.022
0.0015
0.019
0.0015
Output Power
Upper Ram
0.0
0.0
6.3
7.4
Lower Ram
Comment
15.7
24.1
29.7
34.6
38.8
43
47.6
52.2
50.9
51.3
51.9
52.1
51.6
52
51.4
51.3
51.5
51.7
51.2
51.7
51.7
51.9
52
51.8
52
51.4
51.6
50.5
51.3
6230
6230
6230
6230
6230
2600
2600
2600
2600
2600
6350
6500
6600
6700
6710
6720
6720
6720
6740
6750
6730
6730
6700
6680
6670
6690
6690
6680
6640
6630
6630
6600
2600
2700
2710
2720
2730
2780
2780
2780
2780
2760
2750
2740
2720
2700
2680
2870
2860
2850
2790
2780
2760
2750
51.2
6600
temperature alarm
2800 noticed at this
quench
83
Experiment 2
Sample 1
Sample 2
Sample 3
Sample 4
Powder
Water Weight Wt%
Weight (g)
(g)
H2O
0.028
0.0000
0.0
0.023
0.0014
5.7
0.021
0.0000
0.0
0.021
0.0011
5.1
Powder Sample
Coarse GM-407
Coarse GM-407
Fine GM-407
Fine GM-407
11/22/10
Time
9:13 PM
9:15 PM
9:21 AM
9:31 AM
9:51 AM
10:12 AM
11:01 AM
11:50 AM
1:51 PM
1:57 PM
8:20 AM
10:21 AM
1:30 PM
3:40 PM
6:10 PM
9:20 AM
12:00 PM
4:30 PM
5:40 PM
800C 8kb
Temperature (°C)
200
300
400
500
600
700
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
Output
23.7
29.1
33.7
38
41.5
45.7
48.2
48.3
48.2
48.4
48.7
47.7
47.9
48.1
48.4
48.5
48.6
48.7
48.5
48.6
48.6
48.7
48.9
Upper Ram
Lower
Comment
6850
2650
6870
2630
6880
2620
6910
2650
6910
2550
6950
2580
7000
2670
7100
2520
7290
2650
7310
2640
7850
2650 7850 could have
7350
2650 really been 7350
7390
2750
7440
2860
7450
2730
7440
2750
7430
2730
7430
2700
7430
2700
7390 2590 to 2730
7350 2550 to 2710
7350 2500 to 2710
7330
2300 quench
84
Experiment 3
Sample 1
Sample 2
Sample 3
Sample 4
Powder
Sample
GM-407
GM-407
GM-307
GM-307
1/8/11
Date
8-Jan
9-Jan
10-Jan
Powder Weight
Water Weight (g) Wt% H2O
(g)
0.02
0
0.0113
0.0015
11.7
0.0146
0
0.0
0.01
0.0017
14.5
900C 8kb
Time
2:10 PM
2:23 PM
2:31 PM
2:32 PM
3:28 PM
3:39 PM
7:55 PM
10:20 PM
10:22 PM
9:17 AM
12:45 PM
12:46 PM
2:03 PM
2:04 PM
2:09 PM
2:45 PM
3:55 PM
4:12 PM
5:15 PM
5:25 PM
7:07 PM
8:51 PM
9:28 PM
9:33 PM
9:46 PM
10:27 AM
11:15 AM
12:45 PM
2:21 PM
2:47 PM
3:07 PM
6:08 PM
Temperature
Output Power Upper Ram
62
100
200
300
400
500
600
700
800
900
900
900
900
900
900
900
900
900
900
900
900
17.3
21.5
23.5
30.2
35.5
39
44
48
52.9
57
57.5
57.6
57.9
58.4
58.1
56
55.4
55.6
54.4
53.9
54.1
900
900
900
900
900
900
900
900
900
900
900
900
900
900
900
900
900
900
900
53.6
53.9
53.6
53.9
53.9
53.5
53.3
53.2
53
53
53.1
53.1
52.4
52.3
52.6
52.4
52.5
52.6
52.4
85
Lower
8200
2450
8430
8550
8570
8800
8800
8820
8850
8850
8830
8820
8820
8770
8800
8820
8820
8800
8800
8800
8800
8800
8800
8800
8800
8800
8770
8770
8760
8760
8760
8770
8770
2650
2500
2650
2740
2730
2740
2720
2830
2700
2670
2720
1950
2780
2770
2720
2720
2720
2720
2720
2710
2680
2670
2810
2810
2720
2700
2690
2680
2670
2760
2760
Comment
adjusted pressure
temp alarm noticed
increased pressure
adjusted pressure
adjusted pressure
adjusted pressure
adjusted pressure
11-Jan
12-Jan
13-Jan
14-Jan
7:13 PM
7:52 PM
7:58 PM
10:15 AM
12:43 PM
1:48 PM
4:00 PM
7:45 PM
10:30 PM
8:45 AM
11:15 AM
12:00 PM
1:15 PM
3:00 PM
4:30 PM
6:00 PM
7:00 PM
7:45 AM
11:30 AM
3:00 PM
5:50 PM
12:06 AM
9:45 AM
1:55 PM
5:45 PM
900
900
900
900
900
900
900
900
900
900
900
900
900
900
900
900
900
900
900
900
900
900
900
900
900
52.5
52.7
52.3
52.1
51.9
51.9
51.9
51.9
51.4
50.7
48.5
48.5
48.8
49.1
49.5
49.5
49.7
47.4
48.4
49.2
49.4
48.2
49.3
49.6
50.2
86
8760
8760
8770
8750
8740
8750
8750
8760
8770
8750
8720
8700
8680
8690
8700
8700
8710
8660
8680
8690
8700
8700
8690
8680
8670
2760
2760
2840 adjusted pressure
2770
2750
2750
2700
2700
2700
2650
2600-->2750
2660
2600-->2750
2660
2650
2640-->2780
2780
2600-->2750
2730
2730
2730
2730
2700
2700
2670
quench
Experiment 4
Date
2/6/11
Time
Output
Power
6-Feb 4:40pm
21.2
28.7
32.5
33.6
38.6
47.3
100
200
300
400
500
600
700
51.1
50.9
51.4
51.6
51.5
52.3
53.8
52.8
52.8
53
53.7
53.7
54
53.8
54
53.8
53.8
53.1
48.6
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
~42
4:50
5:00
5:10
5:11
5:33
7:13
8:30
9:57
10:26
7-Feb
9:50 AM
11:23
12:40pm
12:43
2:17
4:16
6:11
8:17
11:43
8-Feb
8:39 AM
800C 7kb
Temp (°C)
Upper Ram
Pressure
8100
8200
8280
8300
8400
8450
8460
8460
8500
8490
8450
8460
8450
8480
8460
8460
8480
8430
>8000
87
Lower Ram
Pressure
Comment
2290
2300
2280
2300
2300
2280
2260-->2300
2150-->2350
2300-->2390
2190-->2300
2160-->2290
2250-->2340
2300-->2380
2320-->2380
2260-->2380
2360
2360
2140-->2480
1800 Temperature cycles rapidly
600-1200C. Turned power
off. Temperature reads 78
even though the pressure
vessel is cold. Where is the
Junction?
Experiment 5
Powder
Sample
GM-407
GM-407
GM-307
GM-307
Sample 1
Sample 2
Sample 3
Sample 4
Date
11-Feb
Time
4:45
4:56
5:02
5:12
5:22
8:18
8:58
10:55
11:00
Powder
Weight (g) Water Weight (g) Wt% H2O
0.0206
0
0
0.0148
0.0021
12.4
0.0174
0
0.0
0.0167
0.0022
11.6
Temp (°C)
115
200
300
400
500
600
700
800
800
800
800
800
800
800
800
Output Power
Upper Ram
Pressure
19.5
8150
26.7
33
34
37.9
42
46.4
49.1
49.1
8220
49.2
8280
49.6
8350
49.7
8400
50.5
8500
50.3
8520
50.8
8550
Lower Ram
Pressure
2230
Comment
2260
2240--> 2300
2230-->2350
2300-->2330
2300
2280-->2350
2220
Quenched due to
water leak
88
Experiment 6
Powder
Powder
Water
Weight (g)
Sample
Weight (g) Wt% H2O
407
0.0303
0
0.0
407
0.0281
0.0018
6.0
307
0.0272
0
0.0
307
0.0218
0.0017
7.2
Sample 1
Sample 2
Sample 3
Sample 4
Date
26-Feb
27-Feb
28-Feb
Time
16:45
16:52
17:03
17:08
17:14
17:26
17:35
19:32
21:00
21:28
23:25
23:42
23:53
8:28
9:37
12:07
14:55
18:04
19:18
22:03
22:21
8:43
9:55
10:54
11:04
11:20
12:04
13:40
Temp (°C)
100
200
300
400
500
600
700
800
800
801
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
7
Output
Upper Ram
Lower Ram
Comment
Power
Pressure
Pressure
16.8
25.5
31.6
36.2
40.2
~43
46.7
49.6
49.5
8120
1620
50.1
8230
1700
50.5
8250 1650-->1750
50.5
8300
1700
50.2
8330
1680
50.8
8350 1680-->1720
51.7
8400
1670
51
8400
1650
51.3
8440 1620-->1740
51.5
8440
1630
51.4
8450 1790-->1890
51.7
8450 1820-->1900
51.8
8450 1720-->1800
51.8
8450 1750-->1780
51.5
8430 1700-->1800
51.9
8440 1630-->1820
52
8460
1730
51.8
8450 1720-->1830
51.8
8450 1700-->1860
8450 1800-->1930
52.3
8430 1700-->1780
52.1
8430 1620-->1730
52
8430 1650-->1800
52.1
8430 1550-->1820
52.1
8430
1770
52
8420
1750
100
7820
450 Power outage
around 1:20
quenched run
89
Experiment 7
Powder
Sample
Sample 1
Sample 2
Sample 3
Sample 4
407
407
307
307
Date
16-Mar
17-Mar
18-Mar
19-Mar
Time
1:47 PM
1:55 PM
1:58
2:20
2:36
4:05
6:00
7:45
9:47
11:52
1:00 AM
10:06
11:15
2:00 PM
2:54
6:06
7:52
10:30
12:25 AM
1:15
10:35
11:55
4:25 PM
7:00 PM
9:00
9:55
10:05
11:45
1:00 PM
2:30
4:00
5:00
5:45
6:50
7:17
8:52
Powder
Water Weight
Wt% H2O
Weight (g) (g)
0.0226
0
0.0
0.0223
0.0052
18.9
0.0202
0
0.0
0.0202
0.0045
18.2
Temp (°C)
100
200
300
400
500
600
700
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
800
Output
Power
19.2
28.8
33.1
37
40.2
43.3
46.6
49
48.9
49.58
50.2
50.5
50.6
50.4
50.6
50.4
50.5
51.4
51.5
51.3
51.3
51.3
51.4
51.4
51.1
51.3
51.6
51.7
51.9
52
51.5
51.6
51.6
51.6
52
51.9
52.1
52.1
51.9
52
51.7
51.4
90
Upper Ram
Pressure
8200
8250
8440
8500
8560
8580
8600
8600
8600
8600
8580
8600
8570
8600
8600
8600
8570
8560
8550
8540
8540
8530
8520
8520
8520
8480
8460
8450
8450
8460
8450
8450
8450
8440
8440
Lower Ram
Pressure
1890-->2010
1930-->2050
2060
2050-->2130
2080
2050
2040-->2140
2050
1950
1920-->2200
1930
1900-->2100
1900-->2130
2040-->2120
2000
2000
1970
1950
1940-->2200
1980
1980
1950
1940
1930
1930-->2200
1810--.2100
2000
1930-->2080
1850-->2150
2080
2040
2030
1950
1800-->2190
2020-->2190
Comment
20-Mar
10:45
12:08 AM
1:30
2:00
7:25
8:17
10:30
12:00 PM
1:45
1:48
800
800
800
800
800
800
800
800
800
51.6
51.5
51.5
51.6
51.5
51.7
51.5
51.5
51.7
8430
8430
8420
8420
8420
8410
8400
8400
8400
2000-->2160
2010-->2110
1870-->2200
2150
2080
2070
1960-->2100
2010
1900-->1950
Quench
91
Appendix II: Chemical Analyses
Experiment 1
Dry Coarse Meta-Gabbro GM-307
MgO
Al2O3
SiO2
CaO
MnO
FeO
O
Total
Na2O
MgO
Al2O3
SiO2
FeO
O
Total
Na2O
MgO
Al2O3
SiO2
K2O
CaO
TiO2
FeO
O
Total
Na2O
MgO
Al2O3
SiO2
K2O
CaO
FeO
O
Total
Grt-1.dg.1
Grt-1.dg.2
Compound % Nos. of ions Compound % Nos. of ions
9.88
1.12
9.67
1.10
22.40
2.00
22.09
1.99
39.70
3.01
39.24
3.00
6.15
0.50
6.10
0.50
0.58
0.04
0.60
0.04
20.25
1.28
20.80
1.33
12.00
12.00
98.95
7.95
Ol-1.dg.1
Compound % Nos. of ions
0.73
0.04
26.83
1.19
-0.03
0.00
33.89
1.01
30.51
0.76
4.00
91.93
3.00
98.51
7.96
Na2O
MgO
Al2O3
SiO2
FeO
O
Total
Cpx-1.dg.1
Compound % Nos. of ions
1.27
0.09
13.88
0.76
4.32
0.19
52.04
1.92
0.07
0.00
21.48
0.85
0.15
0.00
7.02
0.22
6.00
100.23
4.03
Pl-1.dg.1
Compound % Nos. of ions
6.82
0.59
0.11
0.01
27.23
1.44
56.99
2.56
0.30
0.02
8.21
0.39
0.23
0.01
8.00
99.90
5.02
92
Opx-1.dg.1
Compound % Nos. of ions
0.45
0.03
29.88
1.64
-0.18
-0.01
55.64
2.05
8.24
0.25
6.00
94.04
3.96
Experiment 1
Wet Coarse Meta-Gabbro GM-307
MgO
Al2O3
SiO2
CaO
MnO
FeO
O
Total
Na2O
MgO
Al2O3
SiO2
K2O
CaO
TiO2
FeO
O
Total
Grt-1.wg.1
Grt-1.wg.2
Compound % Nos. of ions Compound % Nos. of ions
8.14
0.91
9.85
1.13
22.15
1.96
22.45
2.03
42.20
3.16
38.89
2.99
4.75
0.38
5.59
0.46
0.62
0.04
0.52
0.03
21.53
1.35
20.47
1.31
12.00
12.00
99.40
7.80
97.77
7.96
Hbl-1.wg.1
Hbl-1.wg.1a
Compound % Nos. of ions Compound % Nos. of ions
2.59
0.77
3.23
0.91
12.79
2.92
13.38
2.91
13.89
2.51
17.26
2.97
39.45
6.04
41.79
6.10
1.57
0.31
0.14
0.03
11.46
1.88
8.23
1.29
2.16
0.25
0.58
0.06
10.34
1.32
12.41
1.52
23.00
23.00
94.25
15.99
97.01
15.79
93
Experiment 2
Wet Coarse Amphibolite GM-407
MgO
Al2O3
SiO2
CaO
MnO
FeO
O
Grt-2.wa.1
Compound % Nos. of ions
10.99
1.24
22.65
2.02
39.78
3.01
3.70
0.30
0.59
0.04
21.37
1.35
12.00
Total
99.08
7.95
Experiment 2
Dry Fine Amphibolite
MgO
Al2O3
SiO2
CaO
MnO
FeO
O
GM-407
Grt-2.da.1
Grt-2.da.2
Compound % Nos. of ions Compound % Nos. of ions
10.69
1.21
10.93
1.24
22.73
2.04
22.62
2.03
39.18
2.98
39.37
2.99
3.64
0.30
3.86
0.31
0.73
0.05
0.63
0.04
21.92
1.40
21.52
1.37
12.00
12.00
Total
98.89
7.97
98.93
7.97
Experiment 2
Wet Fine Amphibolite
MgO
Al2O3
SiO2
CaO
MnO
FeO
O
Total
GM-407
Grt-2.wa.2
Grt-2.wa.3
Grt-2.wa.4
Compound % Nos. of ions Compound % Nos. of ions Compound % Nos. of ions
10.37
1.16
11.62
1.29
17.57
1.92
22.76
2.02
22.92
2.01
11.19
0.96
39.98
3.01
40.45
3.01
48.88
3.57
5.26
0.42
3.66
0.29
5.89
0.46
0.53
0.03
0.54
0.03
0.24
0.01
20.75
1.30
21.01
1.31
12.72
0.78
12.00
12.00
12.00
99.64
7.95
100.20
7.94
94
96.49
7.71
Experiment 3
Dry Fine Amphibolite
MgO
Al2O3
SiO2
CaO
MnO
FeO
O
Total
Na2O
MgO
Al2O3
SiO2
CaO
TiO2
FeO
O
Total
Na2O
MgO
Al2O3
SiO2
K2O
CaO
TiO2
FeO
O
Total
GM-407
Grt-3.da.1
Grt-3.da.2
Compound % Nos. of ions Compound % Nos. of ions
10.53
1.19
10.27
1.16
22.72
2.03
22.30
2.00
39.19
2.97
39.31
2.99
4.83
0.39
5.35
0.44
0.51
0.03
0.65
0.04
21.23
1.35
20.96
1.33
12.00
12.00
99.01
7.97
98.84
7.97
Opx-3.da.1
Compound % Nos. of ions
0.43
0.03
23.74
1.31
2.00
0.09
52.79
1.96
0.49
0.02
0.09
0.00
19.39
0.60
6.00
98.92
4.01
Hbl-3.da.1
Hbl-3.da.2
Compound % Nos. of ions Compound % Nos. of ions
3.18
0.89
3.08
0.87
13.05
2.83
11.85
2.58
15.41
2.64
15.64
2.70
41.94
6.09
42.87
6.27
0.91
0.17
0.83
0.16
11.63
1.81
10.85
1.70
1.59
0.17
1.40
0.15
10.96
1.33
10.46
1.28
23.00
23.00
98.69
15.94
96.98
15.72
95
Experiment 3
Wet Fine Amphibolite
MgO
Al2O3
SiO2
CaO
MnO
FeO
O
Total
Na2O
MgO
Al2O3
SiO2
K2O
CaO
TiO2
FeO
O
Total
Na2O
MgO
Al2O3
SiO2
CaO
O
Total
Na2O
MgO
Al2O3
SiO2
CaO
FeO
O
Total
GM-407
Grt-3.wa.1
Grt-3.wa.2
Grt-3.wa.3
Compound % Nos. of ions Compound % Nos. of ions Compound % Nos. of ions
10.60
1.18
10.25
1.16
9.94
1.12
22.74
2.01
22.56
2.01
22.74
2.03
39.50
2.96
39.27
2.98
39.35
2.97
5.85
0.47
5.76
0.47
5.92
0.48
0.48
0.03
0.56
0.04
0.52
0.03
21.50
1.35
21.11
1.34
21.24
1.34
12.00
12.00
12.00
100.67
8.00
99.50
7.99
Hbl-3.wa.1
Hbl-3.wa.2
Compound % Nos. of ions Compound % Nos. of ions
3.00
0.87
2.83
0.79
13.00
2.89
13.82
2.96
15.06
2.65
15.88
2.69
40.57
6.06
42.49
6.11
1.34
0.25
1.11
0.20
11.29
1.81
11.57
1.78
1.60
0.18
1.06
0.11
10.22
1.28
10.49
1.26
23.00
23.00
96.09
15.98
99.24
15.92
Pl-3.wa.1
Compound % Nos. of ions
6.66
0.58
0.12
0.01
27.30
1.44
57.04
2.55
9.06
0.43
8.00
100.18
5.01
Opx-3.wa.1
Compound % Nos. of ions
0.42
0.03
24.31
1.34
2.54
0.11
52.65
1.95
0.60
0.02
17.32
0.54
6.00
97.86
4.00
96
99.71
7.98
Experiment 3
Dry Fine Meta-Gabbro: Coarse Area GM-307
MgO
Al2O3
SiO2
CaO
MnO
FeO
Total
Na2O
MgO
Al2O3
SiO2
CaO
TiO2
FeO
Total
Na2O
MgO
Grt-3.dg.1
Compound % Nos. of ions
9.49
1.09
22.16
2.01
38.63
2.97
5.92
0.49
0.63
0.04
21.98
1.41
12.00
98.82
8.00
Opx-3.dg.1
Compound % Nos. of ions
0.53
0.04
23.79
1.32
2.62
0.11
52.42
1.95
0.74
0.03
0.09
0.00
18.10
0.56
6.00
98.29
4.01
Hbl-3.dg.1
Compound % Nos. of ions
2.92
0.81
13.16
2.82
Al2O3
15.39
2.61
SiO2
K2O
CaO
TiO2
FeO
42.57
1.51
11.50
1.98
10.57
6.12
0.28
1.77
0.21
1.27
23.00
Total
99.60
15.90
Na2O
Al2O3
SiO2
K2O
CaO
Total
Pl-3.dg.1
Compound % Nos. of ions
6.43
0.56
27.01
1.43
56.97
2.55
0.28
0.02
9.13
0.44
8.00
99.82
4.99
97
Experiment 3
Dry Fine Meta-Gabbro Fine Area
MgO
Al2O3
SiO2
CaO
MnO
FeO
Total
Na2O
MgO
Al2O3
SiO2
CaO
TiO2
FeO
Total
Na2O
MgO
Al2O3
SiO2
K2O
CaO
TiO2
FeO
Total
Na2O
MgO
Al2O3
SiO2
K2O
CaO
FeO
Total
GM-307
Grt-3.dg.2
Compound % Nos. of ions
9.66
1.08
22.11
1.95
40.56
3.04
6.65
0.53
0.53
0.03
20.41
1.28
12.00
99.91
7.92
Opx-3.dg.2
Compound % Nos. of ions
0.72
0.05
21.67
1.19
5.27
0.23
50.39
1.86
2.97
0.12
0.51
0.01
17.87
0.55
6.00
99.39
4.02
Hbl-3.dg.2
Compound % Nos. of ions
2.24
0.63
15.29
3.32
11.64
2.00
44.83
6.53
0.94
0.17
7.96
1.24
1.21
0.13
14.08
1.71
23.00
98.19
15.74
Pl-3.dg.2
Compound % Nos. of ions
6.86
0.61
0.82
0.06
25.29
1.36
56.78
2.58
0.61
0.04
7.70
0.38
1.14
0.04
8.00
99.19
5.06
98
Experiment 3
Wet Fine Meta-Gabbro GM-307
MgO
Al2O3
SiO2
CaO
MnO
FeO
Total
Na2O
MgO
Al2O3
SiO2
K2O
CaO
TiO2
FeO
Total
Na2O
MgO
Al2O3
SiO2
CaO
FeO
Total
Na2O
MgO
Al2O3
SiO2
K2O
CaO
FeO
Total
Grt-3.wg.1
Grt-3.wg.2
Compound % Nos. of ions Compound % Nos. of ions
10.16
1.16
11.24
1.28
22.03
1.99
22.09
1.99
39.01
2.99
39.12
2.99
3.71
0.30
3.58
0.29
0.59
0.04
0.59
0.04
23.20
1.49
22.05
1.41
12.00
12.00
98.69
7.98
98.66
8.00
Hbl-3.wg.2
Compound % Nos. of ions
2.70
0.76
12.72
2.77
14.47
2.49
43.31
6.32
0.81
0.15
10.70
1.67
1.47
0.16
11.48
1.40
23.00
97.66
15.72
Opx-3.wg.1
Compound % Nos. of ions
0.52
0.04
23.31
1.29
2.14
0.09
52.43
1.95
0.63
0.03
19.62
0.61
6.00
98.68
4.02
Pl-3.wg.1
Compound % Nos. of ions
5.06
0.45
0.11
0.01
29.45
1.59
52.61
2.41
0.07
0.00
11.28
0.55
0.40
0.02
8.00
98.99
5.03
99
Experiment 5
Dry Fine Amphibolite
MgO
Al2O3
SiO2
CaO
MnO
FeO
O
Total
Na2O
MgO
Al2O3
SiO2
K2O
CaO
FeO
O
Total
Na2O
MgO
Al2O3
SiO2
K2O
CaO
TiO2
FeO
O
Total
GM-407
Grt-5.da.1
Grt-5.da.2
Compound % Nos. of ions Compound % Nos. of ions
10.85
1.20
10.39
1.17
23.02
2.01
22.54
2.01
40.28
2.98
39.46
2.99
3.80
0.30
3.83
0.31
0.75
0.05
0.63
0.04
23.36
1.45
22.87
1.45
12.00
12.00
102.06
7.99
99.72
7.97
Pl-5.da.1
Pl-5.da.2
Compound % Nos. of ions Compound % Nos. of ions
6.00
0.54
5.72
0.51
0.94
0.07
0.18
0.01
26.62
1.47
27.80
1.51
52.65
2.46
54.19
2.49
0.21
0.01
0.11
0.01
9.15
0.46
9.61
0.47
1.97
0.08
0.25
0.01
8.00
8.00
97.54
5.08
97.87
5.01
Hbl-5.da.1
Compound % Nos. of ions
3.29
0.92
12.96
2.77
15.47
2.62
42.44
6.09
1.19
0.22
11.80
1.81
1.60
0.17
11.65
1.40
23.00
100.39
15.99
100
Experiment 5
Wet Fine Amphibolite
MgO
Al2O3
SiO2
CaO
MnO
FeO
O
Total
Na2O
MgO
Al2O3
SiO2
K2O
CaO
TiO2
FeO
O
Total
GM-407
Grt-5.wa.1
Compound % Nos. of ions
10.74
1.21
22.41
2.00
39.42
2.99
3.87
0.31
0.76
0.05
22.12
1.40
12.00
99.32
7.97
Hbl-5.wa.1
Hbl-5.wa.2
Compound % Nos. of ions Compound % Nos. of ions
2.98
0.87
2.68
0.87
12.35
2.77
12.66
2.80
14.24
2.52
14.00
2.49
40.52
6.09
40.34
6.19
1.18
0.23
0.62
0.18
11.15
1.80
9.62
1.70
2.22
0.25
1.47
0.21
11.22
1.41
11.04
1.39
23.00
23.00
95.85
15.93
92.42
15.84
101
Experiment 5
Dry Fine Meta-Gabbro
MgO
Al2O3
SiO2
CaO
MnO
FeO
O
Total
Na2O
MgO
Al2O3
SiO2
K2O
CaO
TiO2
FeO
O
Total
GM-307
Grt-5.dg.1
Grt-5.dg.2
Compound % Nos. of ions Compound % Nos. of ions
9.93
1.08
10.00
1.10
23.34
2.01
23.07
2.01
40.89
2.99
40.52
3.00
6.07
0.48
6.04
0.48
0.56
0.03
0.68
0.04
22.99
1.41
21.99
1.36
12.00
12.00
103.78
8.00
102.30
8.00
Hbl-5.dg.1
Compound % Nos. of ions
3.14
0.85
13.82
2.88
16.10
2.65
43.46
6.07
1.29
0.23
11.88
1.78
1.75
0.18
11.09
1.30
23.00
102.53
15.94
Pl-5.dg.1
Compound % Nos. of ions
Na2O
5.50
0.49
MgO
Al2O3
SiO2
K2O
CaO
FeO
O
1.92
25.69
53.95
0.27
9.54
2.34
0.13
1.39
2.48
0.02
0.47
0.09
8.00
Total
99.21
5.07
102
Experiment 5
Wet Fine Meta-Gabbro
MgO
Al2O3
SiO2
CaO
MnO
FeO
Total
Na2O
MgO
Al2O3
SiO2
K2O
CaO
TiO2
FeO
Total
GM-307
Grt-5.wg.1
Grt-5.wg.2
Compound % Nos. of ions Compound % Nos. of ions
10.05
1.11
10.86
1.17
22.85
1.99
22.75
1.94
40.79
3.01
42.84
3.11
5.74
0.45
6.08
0.47
0.62
0.04
0.50
0.03
22.40
1.38
19.71
1.19
12.00
12.00
102.45
7.97
102.75
7.92
Hbl-5.wg.1
Hbl-5.wg.2
Compound % Nos. of ions Compound % Nos. of ions
2.98
0.84
3.13
0.82
12.88
2.78
11.79
2.36
15.18
2.59
17.19
2.73
42.52
6.15
49.97
6.72
1.34
0.25
0.80
0.14
11.33
1.76
8.25
1.19
1.89
0.21
1.33
0.13
10.93
1.32
10.25
1.15
23.00
23.00
99.02
15.88
102.72
15.25
103
Experiment 6
Dry Fine Ampibolite
GM-407
Grt-6.da.1
Compound % Nos. of ions
MgO
10.31
1.20
Al2O3
21.68
2.00
SiO2
38.19
2.98
CaO
4.63
0.39
MnO
0.57
0.04
FeO
20.84
1.36
O
12.00
Total
96.84
8.05
Pl-6.da.1
Pl-6.da.2
Compound % Nos. of ions Compound % Nos. of ions
Na2O
3.56
0.33
6.16
0.55
MgO
0.76
0.05
0.64
0.04
Al2O3
29.49
1.66
26.53
1.43
SiO2
47.60
2.27
55.45
2.53
K2O
0.27
0.02
0.25
0.01
CaO
12.67
0.65
8.44
0.41
FeO
1.69
0.07
1.19
0.05
O
8.00
8.00
Total
96.03
5.04
98.66
5.03
Experiment6
Wet Fine Amphibolite GM-407
Pl-6.wa.1
Pl-6.wa.2
Compound % Nos. of ions Compound % Nos. of ions
Na2O
6.88
0.61
6.17
0.55
Al2O3
26.29
1.41
25.97
1.41
SiO2
56.66
2.58
54.39
2.51
K2O
0.28
0.02
0.12
0.01
CaO
8.03
0.39
9.07
0.45
O
8.00
8.00
Total
98.14
5.01
95.73
4.93
104
Experiment 6
Dry Fine Meta-Gabbro GM-307
Grt-6.dg.1
Grt-6.dg.2
Compound % Nos. of ions Compound % Nos. of ions
MgO
9.35
1.03
10.31
1.11
Al2O3
23.27
2.02
22.09
1.87
SiO2
41.18
3.04
43.48
3.13
CaO
7.04
0.56
6.84
0.53
MnO
0.63
0.04
0.48
0.03
FeO
19.46
1.20
18.31
1.10
O
12.00
12.00
Total
100.92
7.89
101.51
7.77
Opx-6.dg.1
Compound % Nos. of ions
Na2O
0.50
0.03
MgO
25.17
1.35
Al2O3
2.35
0.10
SiO2
53.96
1.94
CaO
0.55
0.02
FeO
19.28
0.58
O
6.00
Total
101.81
4.02
Hbl-6.dg.1
Hbl-6.dg.2
Compound % Nos. of ions Compound % Nos. of ions
Na2O
3.28
0.86
2.67
0.74
MgO
9.46
1.90
12.97
2.76
Al2O3
21.00
3.34
15.85
2.67
SiO2
48.47
6.54
41.78
5.97
K2O
0.35
0.06
3.14
0.57
CaO
9.62
1.39
9.04
1.38
TiO2
0.17
0.02
3.68
0.39
FeO
9.71
1.10
12.32
1.47
O
23.00
23.00
Total
102.05
15.21
101.46
15.96
105
Experiment 6
Wet Fine Meta-Gabbro GM-307
Hbl-6.wg.1
Hbl-6.wg.2
Hbl-6.wg.3
Hbl-6.wg.4
Compound % Nos. of ions Compound % Nos. of ions Compound % Nos. of ions Compound % Nos. of ions
Na2O
3.41
0.95
3.22
0.91
2.40
0.67
2.52
0.71
MgO
12.87
2.75
11.92
2.59
13.28
2.87
13.95
3.03
Al2O3
14.97
2.53
15.90
2.73
13.93
2.38
13.79
2.36
SiO2
42.47
6.09
40.91
5.96
43.81
6.35
44.32
6.45
K2O
1.26
0.23
1.25
0.23
0.80
0.15
0.49
0.09
CaO
11.20
1.72
11.21
1.75
9.96
1.55
8.16
1.27
TiO2
3.06
0.33
3.14
0.34
1.30
0.14
0.62
0.07
FeO
10.93
1.31
11.48
1.40
13.15
1.59
13.87
1.69
O
23.00
23.00
23.00
23.00
Total
100.18
15.90
99.02
15.90
98.64
15.71
97.72
15.68
Opx-6.wg.3
Opx-6.wg.1
Opx-6.wg.1a
Opx-6.wg.2
Compound % Nos. of ions Compound % Nos. of ions Compound % Nos. of ions Compound % Nos. of ions
Na2O
0.70
0.05
0.94
0.07
1.08
0.08
0.43
0.03
MgO
23.51
1.23
22.07
1.20
19.22
1.05
23.91
1.33
Al2O3
5.08
0.21
5.45
0.23
8.43
0.36
2.31
0.10
SiO2
54.86
1.93
52.08
1.90
51.02
1.87
52.23
1.95
CaO
1.15
0.04
2.06
0.08
3.70
0.15
0.32
0.01
FeO
17.17
0.51
16.65
0.51
14.97
0.46
18.87
0.59
O
6.00
6.00
6.00
6.00
Total
102.48
3.97
99.25
4.00
106
98.43
3.97
98.06
4.01
Experiment 7
Dry Fine Amphibolite GM-407
Grt-7.da.1
Grt-7.da.2
Grt-7.da.3
Compound % Nos. of ions Compound % Nos. of ions Compound % Nos. of ions
MgO
11.23
1.28
10.85
1.21
11.45
1.26
Al2O3
22.33
2.02
23.12
2.04
22.92
1.99
SiO2
38.89
2.98
39.88
2.98
41.30
3.05
CaO
3.66
0.30
3.74
0.30
4.04
0.32
MnO
0.51
0.03
0.71
0.05
0.47
0.03
FeO
21.32
1.37
22.35
1.40
20.95
1.29
O
12.00
12.00
12.00
Total
97.94
7.98
100.66
7.97
101.14
7.94
Ol-7.da.1
Compound % Nos. of ions
Na2O
0.66
0.03
MgO
27.81
1.14
Al2O3
0.57
0.02
SiO2
37.85
1.04
FeO
31.09
0.71
O
4.00
Total
97.99
2.95
Hbl-7.da.1
Hbl-7.da.2
Hbl-7.da.3
Compound % Nos. of ions Compound % Nos. of ions Compound % Nos. of ions
Na2O
3.24
0.92
2.75
0.78
3.21
0.90
MgO
12.72
2.78
13.22
2.86
13.44
2.89
Al2O3
15.47
2.68
14.41
2.47
14.63
2.49
SiO2
41.44
6.08
43.05
6.26
43.28
6.24
K2O
0.92
0.17
0.89
0.17
0.86
0.16
CaO
11.32
1.78
10.06
1.57
11.21
1.73
TiO2
1.54
0.17
1.63
0.18
1.42
0.15
FeO
11.12
1.37
12.33
1.50
11.19
1.35
O
23.00
23.00
23.00
Total
97.77
15.95
98.35
15.78
Opx-7.da.2
Compound % Nos. of ions
Na2O
0.54
0.04
MgO
23.16
1.30
Al2O3
2.34
0.10
SiO2
51.57
1.95
CaO
0.45
0.02
FeO
19.05
0.60
O
6
Total
97.10
4.02
107
99.23
15.89
Experiment 7
Wet Fine Amphibolite GM-407
Grt-7.wa.1
Grt-7.wa.2
Grt-7.wa.3
Compound % Nos. of ions Compound % Nos. of ions Compound % Nos. of ions
MgO
11.168
1.238
11.513
1.269
11.07
1.23
Al2O3
22.898
2.007
22.763
1.984
22.88
2.02
SiO2
40.415
3.006
40.712
3.010
40.03
3.00
CaO
3.976
0.317
4.056
0.321
3.95
0.32
MnO
0.556
0.035
0.633
0.040
0.56
0.04
FeO
22.081
1.373
22.221
1.374
22.21
1.39
O
12
12.000
12.00
Total
101.094
7.976
101.898
7.998
100.69
7.99
Hbl-7.wa.1
Hbl-7.wa.2
Hbl-7.wa.3
Compound % Nos. of ions Compound % Nos. of ions Compound % Nos. of ions
Na2O
3.24
0.90
2.84
0.79
2.66
0.72
MgO
13.13
2.80
14.51
3.09
15.56
3.26
Al2O3
15.91
2.68
15.91
2.68
17.30
2.87
SiO2
42.74
6.12
43.82
6.26
45.08
6.34
K2O
0.95
0.17
0.38
0.07
0.09
0.02
CaO
11.23
1.72
8.44
1.29
3.74
0.56
TiO2
1.49
0.16
0.58
0.06
0.33
0.03
FeO
11.23
1.34
12.79
1.53
14.67
1.73
O
23.00
23.00
23.00
Total
99.92
15.91
99.28
15.76
Pl-7.wa.1
Compound % Nos. of ions
Na2O
4.84
0.42
Al2O3
30.40
1.60
SiO2
53.48
2.40
CaO
11.98
0.57
O
8.00
Total
100.70
5.00
108
99.41
15.54
Experiment 7
Dry Fine Meta-Gabbro GM-307
Grt-7.dg.1
Grt-7.dg.2
Compound % Nos. of ions Compound % Nos. of ions
MgO
8.87
0.97
10.69
1.18
Al2O3
23.45
2.02
23.01
2.01
SiO2
42.73
3.13
40.26
2.99
CaO
6.48
0.51
5.90
0.47
MnO
0.51
0.03
0.58
0.04
FeO
19.68
1.20
20.47
1.27
O
12.00
12.00
Total
101.71
19.86
100.91
19.97
Ol-7.dg.1
Compound % Nos. of ions
Na2O
0.93
0.05
MgO
26.83
1.06
Al2O3
2.86
0.09
SiO2
38.56
1.02
CaO
1.81
0.05
FeO
29.65
0.66
O
4.00
Total
100.65
2.93
Fine Area
Hbl-7.dg.1
Hbl-7.dg.2
Hbl-7.dg.3
Compound % Nos. of ions Compound % Nos. of ions Compound % Nos. of ions
Na2O
2.85
0.79
3.07
0.85
3.33
0.91
MgO
13.53
2.90
13.67
2.92
10.49
2.20
Al2O3
14.72
2.49
15.92
2.69
17.95
2.97
SiO2
K2O
CaO
TiO2
FeO
O
43.08
1.19
10.50
1.92
12.05
6.18
0.22
1.61
0.21
1.45
23.00
42.90
1.20
11.21
1.37
10.03
6.15
0.22
1.72
0.15
1.20
23.00
45.73
0.79
10.35
1.60
9.21
6.42
0.14
1.56
0.17
1.08
23.00
Total
99.83
15.85
99.38
15.90
99.44
15.45
Coarse Area
Hbl-7.dg.4
Hbl-7.dg.5
Compound % Nos. of ions Compound % Nos. of ions
Na2O
2.74
0.78
2.99
0.85
MgO
12.59
2.76
13.09
2.86
Al2O3
14.98
2.60
15.51
2.68
SiO2
41.73
6.15
41.31
6.06
K2O
1.34
0.25
1.46
0.27
CaO
11.09
1.75
11.14
1.75
1.66
0.18
1.63
0.18
TiO2
FeO
11.34
1.40
10.62
1.30
O
23.00
23.00
109
Total
97.48
15.88
97.75
15.97
Experiment 7
Wet Fine Meta-Gabbro GM-307
Coarse Area
Grt-7.wg.1
Grt-7.wg.2
Compound % Nos. of ions Compound % Nos. of ions
MgO
9.96
1.12
9.51
1.09
Al2O3
22.54
2.01
22.01
1.99
SiO2
39.72
3.00
39.52
3.03
CaO
6.12
0.50
5.53
0.45
MnO
0.55
0.03
0.70
0.05
FeO
20.87
1.32
20.69
1.33
O
12.00
12.00
Total
99.75
7.98
Hbl-7.wg.1
Compound %
97.96
7.93
Hbl-7.wg.2
Hbl-7.wg.3
Hbl-7.wg.4
Nos. of ions Compound % Nos. of ions Compound % Nos. of ions Compound % Nos. of ions
Na2O
MgO
Al2O3
SiO2
K2O
CaO
TiO2
FeO
O
3.28
12.32
15.79
41.11
1.19
11.21
2.66
11.10
0.93
2.68
2.71
6.00
0.22
1.75
0.29
1.35
23.00
2.90
13.40
14.91
42.06
1.32
11.30
1.81
10.87
0.82
2.91
2.56
6.12
0.25
1.76
0.20
1.32
23.00
3.05
13.29
15.76
41.63
1.43
11.26
2.03
10.55
0.86
2.87
2.69
6.03
0.26
1.75
0.22
1.28
23.00
2.54
13.13
15.12
43.45
1.11
10.81
1.61
11.52
0.71
2.81
2.56
6.24
0.20
1.66
0.17
1.38
23.00
Total
98.67
15.93
98.58
15.93
98.99
15.97
99.29
15.75
Fine Area
Grt-7.wg.3
Grt-7.wg.4
Compound % Nos. of ions Compound % Nos. of ions
MgO
9.92
1.08
9.89
1.06
Al2O3
22.31
1.93
23.06
1.96
SiO2
42.61
3.13
43.78
3.15
CaO
6.16
0.48
6.11
0.47
MnO
0.48
0.03
0.52
0.03
FeO
19.19
1.18
18.40
1.11
O
12.00
12.00
Total
100.67
7.84
Hbl-7.wg.5
Na2O
MgO
Al2O3
SiO2
K2O
CaO
TiO2
FeO
O
Total
Compound %
3.04
13.21
15.35
42.80
1.04
10.53
1.68
11.14
98.78
101.76
7.78
Hbl-7.wg.6
Nos. of ions Compound % Nos. of ions
0.85
2.85
2.61
6.18
0.19
1.63
0.18
1.35
23.00
2.56
13.30
15.01
43.29
1.30
10.69
1.25
11.64
15.84
99.03
0.72
2.86
2.55
6.25
0.24
1.65
0.14
1.40
23.00
11015.81